How rare is it to find a SL convertible 1972-1989 in good driving shape for $9000?

I went to cars-on-line.com and they had almost 100 sl's in this price. If I bought one of these, what am I looking at most likely as far as maintence and repair costs and such?

8-10k is all the money I have to spend on a car, and I only make 9 dollars a hour at work. I was thinking about getting a 70's model Corvette but when I seen these convertible SL's at these prices it made me curious. I would prefer the SL over the vette, I'm just wondering if it's something I can actually afford. I mean I'd hate to buy a 10,000 SL and get it home and have it break down 6 months later and then have to put 5k into getting it runing again. I'm just trying to be realistic and make the best choice between a old vette or a old benz.

So do you guys think the SL's are out of my league?