I recommend getting the 115 rear sway bar links, They have a metal shaft.

Update
 

Got it fixed!:D I was able to get the rear sway bars local. I really have to plug Foreign Parts Specialists, they had it in stock for 15$ and they are within a mile of the house.

When I pulled the rear tire off it was pretty obvious what the clunk, and shimmy were as the wheel spacer had split right where the hub centric portion meets the body of the spacer:eek: I've got the 15 inch wheels on it now and I will never be running wheel spacers again. I'm a little surprised though as those were the billet spacers made for this model vehicle, and the rims they went on were also Mercedes rims, they seemed to fit really well.

My best hypothesis is that I had two things wrong at the same time on both ends of the car with very similar symptoms. The original vibration was the old rubber bits on the front end of the car, but at some point prior to me replacing those parts one of the rear wheel spacers had split, causing a similar shimmy at the same speed. Very weird.

Anyways the shimmy is gone, so I took out for a test run at highway speeds and the car seemed very happy, my 5 minute test run ended up about 20 minutes though because it was nice to have it running again. Thanks for the help everybody!

Yep, spacers are generally a risky proposition. Unless they are very costly and manufactured with .0005" runout, they're going to cause problems.

I wish I had noticed that tidbit in the first post.

Ditto that would have been useful info. I tried a variety of combos before I just came to the realization they are always a bad idea.