car step repair

Various step type available from various detail parts manufacturers. They are available through Walthers and many others sources. You can also make them from wire or flat brass stock.

Staples

Many people use staples to repair stirrups.

http://model-railroad-hobbyist.com/node/22752

http://model-railroad-hobbyist.com/node/16254

http://model-railroad-hobbyist.com/node/22952

"repair or replace these

   This is a great basic skill to learn. New thin stirrup steps is the single most apparent  improvement that can be made to many plastic cars. I generally cut them off all cars that came with thick stirrups and install new thin ones. As Alconut notes above there are many types to choose from. They will usually require drilling small holes. I usually make my own from thin brass strips or wire then melt them in place with a soldering iron but it takes some practice.....DaveB

I like using...

stirrup steps from A-Line:

http://www.ppw-aline.com/detlfrgt.htm

They come in various shapes, and are widely available.  As described on their site, these parts "offer the perfect balance between prototypical appearance and durability on virtually any HO scale freight car."

Detail Associates makes some

Detail Associates makes some really nice sill steps, but you have to be careful as these can be fragile. I like to use flat brass stock to make mine, very durable.