Greg,
The PCMs can still be had from the dealer. I paid a little over $200 plus shipping for mine about 2 years ago. A specialty automotive electrical shop can rebuild them but they're very pricey. I was quoted $400 when I was looking at options to replace my PCM. As far as charging, you could do the external regulator conversion.
Aloha,
Matt
junk the pcm and go with out it. . voltage regulator and speedo froma early first gen . . you only need to get 12v at the fuel shut off . . if you gut it then you only need to have your grid heaters and your starter. . etc. . all mechanical is the way i would go...
Later
Deo
Rostra electric servo cruise. Works better than stock. I also won't drive long distances without cruise. Or short ones either.