*Whew*
I'm not a dripper type, really, and I'm not sure if parts are avail. I think I'd email
vapordna and ask. That's a Progect Sub Ohm topper, and VDNA generally knows what they're doing. Plus, it's sold as a competition top. I would think it odd if it didn't come stock with a PEEK insulator. PEEK is pretty tough plastic; if you're melting that, you've got some serious heat going on. If they have parts, fine:
buy several and replace as needed. If not... hhhmmm... Grainger sells PEEK rods. You could make one, even without a lathe, with a drill and a Dremel if you're good with your hands. If it's really PEEK-- ask when you write, it doesn't say on the website-- and you're melting that... double hhhmmm... I think I would bring the base to a local pottery
shop and pay them to fire you a ceramic one next time they heat the kiln.