Mac Minarelli go kart engine

Hey all, I'm new around here but I have recently acquired a pair of 125cc Mac Minarelli 2 stroke liquid cooled engines for enduro karting. I have been trying to find it least a water pump, but haven't found hide nor hair of any parts for these whatsoever. I found a thread stating that there are very few of these engines around, and I was wondering if anyone here knows much about them. There's enough parts that came with these for years to come, as I have four and a half spare cranks with conrods, and more clutch parts than I know what to do with. But the scarcity of any information on them concerns me, as I'm not sure what the gearing is in the transmission (nor do I know how many ratios there are), let alone where to find gaskets for these. One block has a star in the serial number as well, and an additional coolant outlet. I picked them both up for $300 including shipping, and they appear to be pristine, minus the dust. I'm going to be building them for my friends and I to start into karting. Thank you all for your help!