Try Bronco Connection in Nebraska. They always seem to have a few early model tubs around. You need to give them a call, they don't have everything listed on their site.
I got a '71 tub that's in better shape than most of the one's I saw out there. I replaced the major rust areas, but there's a little more left to tackle. I have the panels for it and the wheel wells are uncut. I'll let it go for cheap. E-mail for info. Ken.