I had a similar situation. I cracked the rear glass in my 1988 560SL. Call the dealer: $810 for the glass alone. I can have it installed for $930.

I called a local Mercedes salvage yard/parts dealer. Nobody else makes the glass, but he can sell me a new one for ~$530 (from Mercedes). Or, he can sell me a used one for $350.

I thought this was still a lot of money to swallow for a hardtop that's only on my car for 3 or 4 months a year. So, I started looking for entire hardtops on eBay. I didn't care about the color, since my plan was to remove the rear window and install it in my hardtop. I quickly discovered that shipping an entire hardtop was in the $200 neighborhood, so that wasn't going to make it any cheaper than the $350 option above.

I ended up limiting my hardtop search to areas that I was willing to travel and pickup the hardtop. I ended up buying a beautiful silver hardtop in the Dallas area (~3 hrs away). When I get the time (my hardtop isn't on right now anyway), I plan on replacing the rear window on my hardtop and parting out the rest of the silver hardtop. It cost me less than $200, including gas.

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Mike Heath
1988 560SL Black/Palomino
1988 300SEL Black Pearl/Burgandy
1984 500SEC Anthracite Grey/Palomino