The 2894 is a very normal movement to use as a base. It's better and slimmer than a 7753. Just look at the number of seconds-at-three watches out there, like the Monaco or the Speedy reduced.
I glued my gen tube into my UPO and it came out. I glued ity again and it came out again. I araldited it and it came out. I araldited it again and it's solid.
The first aralditing cleaned out the crap and paved the way for the second to work.
If you don't have access to welding, don't give up with the glue.
Why did I need a gen crown/tube? Because the UPO tube stripped, of course.
Not quite. At 12 years, it's half as radioactive, not half as bright. :-)
Oh, and sure you can charge it. Tritium paint isn't just tritium; it's tritium, a phosphorescent and a luminous element.
With all watches like this, you're buying the seller.
If the seller is trusted, it's plausible. Its a hokey story, but if the seller is genuine, you're all set.
Oh, if it is indeed tritium, it's 99.9% genuine. You can't get that paint easily.