I expect a lot of the parts shortages one may be seeing now are the result of the same "supply chain disruptions" that are making my local supermarket look more and more like ones I recall back in the happy socialist workers' paradise of East Germany back in the '80s. We've all noticed that some of those shelves are looking a bit bare, right?
Whatever parts your local dealership may decide to stock (or not) in future to cater to Bullet owners, who by now are mostly doing their own servicing anyhow, I expect parts for those UCE Bullets will be generally plentiful for some time to come. Same for the old Iron Cylinder Engine. Perhaps not so much for the rather short-lived intermediate AVL versions, which even pre-Covid were being reported as becoming sparse or "sketchy"--though very often this seems to have been a matter of other models' bits being sold or advertised mistakenly as being suitable for the AVLs.
Precise historical production figures for the long run of Bullets of various models are hard to come by, but here's an excerpt from a recent Bloomberg article that fairly well sums up the growing scale of production of those last models of Bullets under Eicher ownership:
"The new Bullet, plus a model called the Classic that leaned even harder into the 60s aesthetic, went on the market in 2009, catching the middle of this long financial tailwind. That year, Royal Enfield sold about 52,000 motorcycles. In 2012 it was moving more than 100,000, overwhelmingly in India, a number that had almost tripled by 2014—representing more than enough revenue to finance other upgrades to the product line. In its last financial year before the pandemic struck, the company sold about 824,000 bikes globally. Harley, by contrast, shipped about 218,000."
Source: https://www.bloomberg.com/news/features/2020-10-14/india-s-royal-enfield-motorcycle-is-coming-after-harley-davidson-hog (Good article, by the way)
Prior to the UCE, one hears rather vaguely of production figures for the old "Iron Bellies" of perhaps about 30,000 per annum at their peak...but with production of that model more or less unchanged for over half a century since 1955, that's still a helluva lotta bikes that'll need a gasket or grommet now and then. Factor in the fact that in India, far more than in the USA, a Bullet is an "aspirational" and even multi-generational symbol of success with a certain Harleyesque element of patriotism mixed in, and I personally have little fear my old thumper will get what she needs for at
least as long as I'm able to swing a leg over her.
Will one still be able to get a brand new $24 OEM carb with all the fixins or a $14 sidestand assembly delivered free to one's door from far yonder in 20 years? Maybe...maybe not. But I can still get any parts I need for my '57 Zündapp Bella scooter, so I'm certainly not gonna lose any sleep about my Bullet.
I'd say get one. In fact, if you can, get a nice "ultra-primitivo" Iron Barrel to tinker with. They do have their own simple and unimpeachable virtues as true engineering fossils, and the fettling's all part of the fun.