I've got a TCI '32 chassis and I'll be using Vintique rubber bump stops. As you can see the chassis has the C notch and these fit perfectly up in there (not installed yet), you just have to bend the tab a little to match the curvature. The rubber is pretty hard but not like urethane and it can be cut down to fit your needs.
You can see the need for bump stops on mine, if I hit a bad whoopdedoo and bottomed out the panard bar bracket would hit the upper 4 bar
Anywho the part number is messed up but it looks like ??-5783. Here's a pic.....