Its not even available on Steam apparently, the original edition which also used GFWL for online play is still $20 there.
http://impulsedriven.com/ssfivae?AFFID=eml_i062812_10&CID=eml_i062812_10
http://impulsedriven.com/ssfivae?AFFID=eml_i062812_10&CID=eml_i062812_10