I have heard of a company called Jeffco that makes similar transmissions specifically for street cars. The guy who runs the place used to work for Jericho I think (or was it Lenco?). They actually are made to fit in the stock TH350/400 or PG spot on first gen cars. They feature alluminum parts, are cheaper, and are four speeds. I haven't seen one running, but they are supposed to handle 1000 horses.
Bad things I have heard about the Jericho is that it is a real pain to downshift while driving. I don't know why that is, but it is what I have heard. The article I read on the Jeffco trans said that it was specifically made to be easier to downshift than other brands so that it would be more of a street trans.