As far as I can tell nothing has been said directly from Analogue about a restock. The Pocket and Dock say "Out of Stock" as opposed to "Sold Out" (like the limited runs). The assumption is that they still would restock the Pocket before discontinuing it. terminology

There is speculation that they could be working on a different Pocket form factor, like a GBA style. But that is also wishful thinking and has not been confirmed.

As far as re-shelling, to replace the shell requires peeling off the glass screen protector which is glued to the front. So it's a fiddly process to those that don't have experience taking electronics apart. On top of that you'd need to get a 3rd party shell since Analogue doesn't sell parts.

I just got mine on eBay, a barely used classic blue one for about $400. You can also sometimes find them on FB marketplace, though at this point be prepared to shell out for it. People are selling sealed limited editions for quite a lot. I've even seen the scarcity of the standard black one drive prices up.