If all else fails, Amazon sells it ...$6.53, not including shipping.

Auto parts stores that cater to the auto body shops in town should carry MEK. Popular for washing out spray guns. It is also used by the marine business with their fiberglass work. If you live near a marina they should have some. Most popular lacquer thinners are usually a high percentage of MEK so may work as a substitute.

Methyl Ethyl Ketone

Same issue down here is Australia - I got mine from the local paint store. 

Perhaps have a look in yours.

Two that I've used very successfully are:

Plastruct PLASTIC WELD (Walthers # 570-2), and,

Hebco TENEX 7R (Walthers # 731-7).

Same issue down here is Australia - I got mine from the local paint store.

You might not find it in a hardware store, but if you go to a paint store, you should find it.  By the way, if you are not sure what to look for, MEK stands for Methel Ethyl Keytone.
 

MEK  vs MEUS

I work for our municipality and one of my "other assigned duties"  is Director of Disaster Social Services - meaning that when something goes horribly wrong it's my job to make sure that the needs of all the displaced and distressed people are met as best as we can in our small town.  We train annually for a job we hope we never have to do. 

Anyway, one of our frequent exercises in disaster preparedness training is the chemical disaster.  The scenerio usually contains a disasterous spill of "Ethyl Methyl Ugly Stuff" .   Now I know what they are referencing.  And I won't forget what I'm looking for (well at least not the M.E. part). 

BTW the closest I've come to a real chemical disaster was a train derailment that happened right my eyes as I was cutting my grass many years ago.  A small train pulling about 20 car loads of jet fuel tipped over about 250 yards from my house.  I had stopped to watch the train pass (hey I'm a train buff) and I noticed it wobbled a few times then one by one the tankers just tipped over like a house of cards. 

I did learn that jet fuel is not nearly as dangerous as it sounds - seems it has an exceptionally high ignition point so no real danger of fire.   Mind you we did not have to kill any weeds in the section along the train track for many many years as it also turns out that jet fuel is not a good fertilizer.  Hate to think what it did to our ground water but they said that the amount that spilt was not that great as the tankers did not rupture.  Fortunately the train was going very slow.  No displaced people to worry about so no call into my office for disaster social services. 

M.E.K is an Epoxy Paint and catalyst activated resin thinner and lacquer Paint Stripper.

M.E.K. is used to degrease Metals and remove oils from its surfaces. Regular Oil base and water base Paints literally Break down and M.E.K doesn't thin but actually dissolves and separates the base colors and bonders in them which makes M.E.K. a great product for removing both old dryed and fresh lacquer paint.

M.E.K. will strip most paint on cars and trucks but, it Take's a lot and there are less expensive products made for Stripping that much paint.

M.E.K is also used as a solvent base adhesive with plastics. So use care on what you try to strip or clean as most plastics used for Model Railroading will also melt along with the paint if you try stripping them with M.E.K., But  M.E.K.works great for stripping everything off solid brass Models.

As far as Paint stores I would consider them the #1 source for M.E.K. Most House Painters will and have used M.E.K for years to revive and Clean all paints from Natural Bristle type brushes. Just Don't attempt to clean Nylon brushes in M.E.K because the brushes bristles will dissolve and leave just the handle and metal clamp behind (I found that out the Hard way about 45 years ago cleaning my fathers paint brushes he still gives me a hard time about those 4 brushes coming out of the bucket with no trace of the nylon bristles that was on them).

MEK is also used for PVC pipe adhesive (actually solvent).  It can be found in big-box store plumbing departments... dispensed in round metal cans with wand-type applicator. 

Often blended to a Gel consistency.  This way. it does Not Flow between plastic parts... it Sticks to the surface.

If all else fails, Amazon sells it ...$6.53, not including shipping.

Good advice for guys that live in the US perhaps, but shipping that to Canada, (where the OP lives) could be costly to the point of absurdity.

FKD,

I got my MEK from General Paint, (in Regina,SK).  Not every location carries it though.  It is more an industrial painters solvent, (so I am told).  Even General Paint does not keep the MEK on the shelf though.  I had to ask for it.

The only size they sold was the gallon can.  I paid around $19.00 for the Gallon.

Edit: I tried the BIG BOX places and hardware stores before being told that I would need to go to General Paint to get it.  It's like a controlled substance almost!

Well, at least a regulated one. MEK is a volatile organic compound and as such is regulated by VOC laws. At one time it was even considered to be a HAP which requires reporting in the US. It disappeared off store shelves during that time. It has since been de-listed as a HAP and has reappeared at stores albeit not as easy to find as it once was.