I THINK this is a melling cam, and the number that's coming to mind is 22203, but going off memory there so I could be wrong. pulled from my buddies small block after about 400 miles or so, was going to use it in my next build. and my buddy didn't build the motor, he just had a box end from the cam, given to him by the builder.

casting marks:
EP1 (behind fuel pump lobe)
C5, D5 (in front of second journal)
10, L4 (behind second journal)
CWC (behind fourth journal)

Stamped on back:
MP P

White daub of paint behind fuel pump lobe, orange daub of paint in front of distributor gear.