I have one that is rebuilt with new pistons,cam,bearings )main and rod bearings). Just a shortblock no heads. I would take $350 for it but shipping may be a problem.
I have a running 455 that is in my car. It's in storage right now but I'll be driving it home in a couple of weeks to start the resto. 6x heads, Holley Dominator Intake and Holley carb. Was in the car when I bought it. I don't know anything about the internals. If interested I'll get casting numbers and date codes.
If nothing turns up, have a long block out of a 68 GTO in my way. Sat outside for years before i got it, so need complete go thru. Gon'a disassemble/check over it this wkend if nothings else pops up.