I'm in the same boat.... There was a guy up in Savannah i think it was, that contacted me a while back through this site, that had one. i wasn't in a position to get it at the time though. hopefully he'll contact you.
I've been looking for something not RV too, like a futon, that either fits or that I could easily modify. So far I haven't found a lot. A couple things from Ikea that I want to check out the next time I'm there, but I have my doubts they'd hold up without some serious modification
Anyway, good luck to you