On Thu, 18 Jan 2018 12:01:36 -0800, Electric Comet
wrote:

mine is a skil saw from the 70s i think

I bought my Crapsman RAS in '76.

seems to run fine

am curious because i wonder if they can become unsafe to use in the
electrical sense and what to do besides replacemnt

Not likely. If you're worried about it, use it with a GFCI.

guessing that replacement parts might be hard to come by

Likely, though you'd be surprised what you can find in an good
hardware store (and, of course, online).