Chinese look a like Little M block
There is one of our members in Monee Illinois that sells Little M blocks for real resonable price. I bought one, am using it, have never seen one advertised cheaper and he is within my driving range to pick up.
I bought Pro Comp BBC valve covers and they were 1/4" short in length and would not hold a gasket without leaking. I don't think I would buy a PRO COMP Chinese block or heads after that.