Alternators would have been a pretty new concept in 65, most other manufacturers were still using generators during that time frame. I would suspect a modern alternator and a matching regulator would probably provide as much (probably more) power as that heavy duty 65 version.
Unless your going for the date perfection thing, I'd just go modern, finding something that may well have been an after market product to begin with, or a 1 or 2 year optional part production may prove to be extremely hard these days. Gene
Thanks Gene, that's what I just figured out. I've found a couple of police cars with my set up. Ive found a nos regulator and the corresponding 65 amp alternator. The problem is that I don't have all the bracketry and I believe it may require a idler pulley. I'm going to try and find a 65 engine harness for a stock application and use that for a regular alternator while I search for the old stuff. Its a unique truck with a factory spot light, so I'd like to eventually put it back to its original condition at some point.
