Wow. Looks like an LSK to me as well. I'll check to see what I have.

I just rebuilt my LSK and am putting it back into service. I have several Piston/Sleeves left. 1 mod and 1 standard. Same with the Black Magic engine.

I'll post pics of the box for my LSK and I think I have the original Brand New Head that I removed in order to put an after market one one that I could use/abuse. You know what I mean. :we