You might check here.
I do have a queston. What did the engine originally come out of? That could make a difference in finding the right part. The reason I ask is that you mention that it's a hydralic cam engine, which leads me to beleive it's either a Passenger car w/Powerglide, or it's a '58-'62 block. The earlier blocks usd in trucks and std shift cars were mechanical cams, and were not drilled for hydralic lifters until '58.

Bill Burmeister