Ok Houston. I'm gonna try to stump you.
A few years back Novarossi made a 6-port blue head .21 called the N21B 2000, not the N21B 2001. I had a runaway right after I broke in that 6-port engine which scored the piston and sleeve pretty bad. Do you have any idea if a p/s from another engine will work in that 6-port case?
It's not a big deal since that engine is sitting in pieces and has been for a year now. Just wondering if a unique mill could be had by combining parts.
Good luck.