I do have a 250 Matchless in quite good condition that requires some cosmetic finishing or could be used as is,
It is in one piece and I have been in the process on a 12v conversion which is more or less done with a new loom. It's still on points so if you wanted to go electronic an inexpensive "box" would finish it off but keeping the points.
I currently have the wheels off as they have been painted in the past but the cost of a rebuild is a bit silly so I am at a stalemate.
Lots of history with it and depending on how picky you are could be up and running in a few weeks or would make a very easy full restoration.
I might consider a "normal" bike / large scooter but would prefer a diesel enfield or similar.