Keep looking on craigslist or in local scrapyards for B210's. It took me two years, but I found a guy selling a trashed B210 for $1800. I drove it home and pulled out the engine and transmission, and sold the rest to a scrapyard for $200. That's not cheap, but for my situation it worked really well. (I needed the whole emissions and carburetion system intact.)
My plan had been to swap my four-speed into the B210 but it was in such bad shape I didn't feel right selling it as a driving car.