If you have no luck finding a supplier, they a welding supply. The tips are very likely stainless steel 3/32 welding rod wire. They come in three foot sections. If you have a portion of a tip left, take it or the pounce itself in with you tp make sure. You will have to cut the pieces, of course, but that should work.
Pacific Coast sign shop is where I bought my electro pounce in 2005. When I called last week, he told me that the FMS company had stopped making the machines for a while but heard a rumor that they were going to make them again. So he doesn’t have electropounce machines but he carries the needles, “electric pencils” and cords.
Several months ago I was trying to get more needles from McLogan, and they weren’t helpful at all. I called a few times, one salesperson wanted to make sure my machine would work with their needles, I sent photos, etc, and they never called.
If you need parts, I would go to Pacific Coast Sign.