[MrFixr55]

Look up Remington wire on eBay. The wire that you want has a UL1015 rating. I use 18 gauge which is overkill for a lot of it, but for the grid and plate you can certainly use 20 or 22 gauge wire. For most under chassis, I don't get too fancy trying to match the original wire, but if you are working on a high value radio, that is a consideration.

Search the forum for "rubber insulation" there are some relatively recent posts of disconnecting one end of the wire and slipping spaghetti or heat shrink tubing over the wire after knocking off the disintegrating rubber insulation. this willl save some time.