Melda Productions recently came out with such a plugin, the MTurboComp. I haven't tried it, but their stuff is usually decent if you can get past the ugly interface. http://www.meldaproduction.com/MTurboComp
FabFilters C2Pro has quite a few modes. Clean, classic(1176ish), Opto, plus a few others. I love this compressor. It's not meant to emulate those classics exactly, but it is quite flexible and can be as subtle and clean as you want or it can squash and destroy. The side chain functions are very powerful as well. Highly recommended.