Dear Lost;
The 292s were "de-tuned" at GM as a 'SMOG' maneuver (compression lowered) back then; as were many other Mfg. engines. There were 'replacements' for a while, but not now.
You really should get a forged set (flat top) like Larry mentioned. The ones on e-bay are cast and dished.
See what they say at Ross.
Good luck.
PS: Make sure the block face hasn't been 'cut off' before you order anything.