No, unlike Rolex, there has never been a consistent source of any Panerai parts. There are random parts on forums and open areas, and periodic stock drops from some service technicians. But these are not sources of systematic availability. Panerai has to hunt for any gen parts.
I have been looking for months. I see them occasionally on eBay and chrono24, but they’re expensive. Years ago they seemed more available, seem scarce now. Be careful, there’s a slytech dial on chrono24 for example, I believe it’s fake.
Panerai are REAL big on the Homage forum. I recently started a couple builds of my own, but it seems like a lot of those guys make their own dials.
I made a couple Rolerai dials for my own use, then bought a couple from Athaya, and am back to building my own dials, although I haven’t got much past the planning stages. I don’t think Belkin is going to lose any sleep over what I churn out, but they’re fairly simple designs, with less “precise” dials than a Rolex (ie, the 3 piece dials don’t have fonts and spacing that’s as tiny as a Rolex), and seem like a fun project.
Athaya has some, and there are some sterile ones in AliX, but there’s a lot of damn nice DIY ones and they seem fairly easy to do.
Check out the Italian section of the Homage Forum for some ideas. They seem to mostly focus on the early models, 3646 and 6152/6154, but there’s a little bit of everything there.
Belkin does wonderful work and can make a lot of dials for Luminor’s, Radiomir, vintage etc… but I assume he can’t do most submersible dials, like 087, 064, 024 etc… I’ve never asked, but I’d love to be proven wrong. These are the types of dials I’m most interested in. Especially t-dials.