I see lots of 'em on ebay, some at very attractive prices. Other than that, do you know offhand if the power resistor you mention is used for the transport motor, or the autofocus motor (or maybe the whole shebang?) (It's been a while since I've worked on 'em.)
Carousel 750, but it's not the solenoid tip, or at least not only the tip. There is a large ceramic power resistor on the motor, and that has flaked off much of the insulating ceramic, including the markings, and there appears to be a lot of corrosion and such in it. Since I lived in Florida, South Carolina, and Germany after I got it, and it spent a lot of time in storage and on ships crossing the ocean, I think it's toast. I keep an eye out in thrift shops for another one, though. Of course I've been carting it around since the early 80's. It's quite possible all the thrift shop Carousels are gone, by now.
I can try to find my fiches and see what they say about it, or, I can get on the line with some guys still in the trade and ask some questions. I wouldn't doubt that one of 'em would either know the value of that resistor, or, be willing to take a VOM to one to measure it for you (or, sell you one for a reasonable price -- shouldn't be more than a buck or two I'd think).
One other "slick obsolescence 'feature'" I remember is the B&H "cube" projectors. They used a *tiny* "fusible link" in their transport motors. Looked like a small metal diode, and was laid right on top of the windings. The idea was that if the motor overheated, the link would melt (internally), and the thing would shut down to prevent damage.
Of course, they tended to blow for "no reason at all", and, just to make life interesting, they only shut down the motor, so, I ended up replacing a lot of melted shutter blades (two that closed in on each other between slides), that didn't like an environment with a HOT lamp, and NO cooling! LOL, "engineering", LMAO!
The heat-fuse was an easy replacement, IF they brought the thing in before they roasted the rest of the projector. I think it cost a buck or so, you can buy them from pretty much any electronic parts supplier. Lots of things use 'em. I don't think Kodak put anything like that on their motors. I never saw one in that condition.
They don't make Carousel projectors anymore, which IMO is a bit of a tragedy. They were real workhorses, very reliable, gentle on the slides (gravity feed, unlike the side-feed straight-tray types, which, if anything went wrong, would destroy your slide while trying to insert it into the projector). Properly maintained they ought to last a lifetime. If parts ever do become an issue for you, well, that's what "broken projectors" are for. Nothing like a nice "donor body" or two to keep on hand.
PS: If your projector seems to be working (i.e., the motor powers up when you turn it on), but it doesn't operate when you press the advance button, then it's pretty much got to be the solenoid tip. (Sure, it could be something else, i.e., a burned-out solenoid or somesuch, but I've never seen one.)