Thanks for the speedy info. It may be an old version of the SeaLand 511 or the platform may also be part of the blackwater tank. I flunked shop class.
Tomorrow, I may throw the porcelain bowl and lid parts back inside "Lil' Miss Sunshine", hook 'er up, then drive to an RV place 30 minutes away (yes, that's the closest choice I have) and get the RV repair guy to take a look.
I'll take Vaseline for the reaming he'll inevitably do to me.
Really, it may just need some kinda water valve, the one in it that failed was some kinda Mansfield Triple somethingorother that I could not find a replacement for and i guess the rest of the potty is all functioning - - - just ancient.
I'll update with whatever info I come up with.