zepherman - you can get an R302 (4 bolt) block from Keith Craft for around $1,600. This will be in cast form and will need to be machined.
You can get them from other places as well - I think Coast has them too. If you're going to spend the money on a 4-bolt, you should ensure that a reputable shop does the work. If money is no object, then just give the guys down at Bennett Racing a call - these guys are very expensive, but put out some of the baddest Ford smallblocks in the country!
E