I bought this maybe 10 years ago and used it for my living room amp. A few weeks ago our trailer broke so I grabed the PR and a Pro Jr. and an extra stereo multi FX and played the Gig and the 2 in stereo worked great. So I decided that I'm going to start using those 2 amps an FX for small gigs. Well I took the PR to my Tech and had him go over it mostly thinking that it'll need a cap Job but they were still good after 47 years? The original tubes were good only the Rectifer tube was a little weak but I have a SS one for it that will give me 4-5 more watts but it's already pretty loud because it has a Altec 417 12" speaker in it.
The SS rectifier will work but it'll put a bit more stress/wear on those power tubes.
You might consider doing a retube now and saving those originals while they still have some life. That's a great mojo story ("...and the original tubes still work!") as opposed to "and then I turned it up to 8,and after a few minutes...".