Kawboy ! I have never a seen a set of float valve needles with a Viton tip in these Mikuni's. . All have been solid. However, all that I've seen I've believed to be OEM's.
1980 KZ 1300 sr# KZT30A-009997
Always High - Know Fear !
You were asking about a replacement solenoid. I would imagine that one from a KZ1000 would be fine. As an example, this one from EBay.
EBay KZ1000 relay
$10 US.
I would imagine you fried the pull in coil winding from all of your attempts to start the bike
