No need to order off line or anything.Just use your basic high temp gasket sealant from the auto parts store.I use the orange stuff that dries like rubber.Stay away from that shit that doesn't dry.That stuff is junk for cases IMO.
i use the orange stuff for all kinds of shit...sealing the rubber grommet thing on the stator wires at the case,reeds,the rubber gasket for the stator cover,tacking the rubber o-rings on coolheads when the fuckers won't stay in place..