420 sel suspension

[SCOTTFISH]

I have searched the archives and I am wondering if someone can verify what type of suspension my 90 420sel has? From the reading, I think it has just standard shocks in the rear. My rear seems to bounce a little more than I would like on the road in the rear, so I am trying to get some sort of picture of how much the repair will cost. If they are standard shocks in the rear, Importec.com has Bilstein Shocks for $69 per shock. Can someone verify my suspension? Oh, you can tell me your opinion of my rear suspension if you would like. I push down on the fender and the back end will bounce slightly 2-3 times after I let it go. It, of course, does not just keep bouncing like the shocks are completely gone. It is a slight bounce. But, when driving sometimes it feels like the back in bounces(gives you the feeling the car is hinged in the middle). Is this a sign the shocks are worn out or are going? The car has 106k on it. What do you think?