Replacing the tuners is a fairly simple task, but there are a couple of factors that can complicate it. I'm not familiar with those tuners but they're either a direct replacement for the smaller Kluson holes that are stock on that guitar, or someone reamed the holes for the larger posts. So hopefully someone can identify what specific model those tuners are and the size of the bushings they use, so you can figure out what kind you need to get to replace them. If someone reamed the holes, you'll need to get conversion bushings if you want to go back to the Kluson style. Second thing is wether the bushings are the push-in type, or the screw-in type like the Govers. When I removed the stock Klusons on my 480 I had a hell of a time getting the old push-in bushings out.
If i desired, is it a simple replacement job to put on more period like Grovers like these, or are the Schallers pretty good anyway?
I'm not familiar with 70s-vintage Schallers, but the quality of the Schallers on current Ricks is top-notch. So I doubt there is any functional need to replace the 70s Schallers on this 480 - the only reason to do so would be for looks.
The refinished 480 I picked up in August has smaller-size Schaller tuners installed (instead of the original Klusons). I guess they were changed before the guitar was painted because the chrome is potted on these, but they function just fine. The R tailpiece chrome is also potted. The guitar was painted maybe 5 or so years ago, but the rough chrome pieces would seem to pre-date the re-finish. They also installed these Schallers with little black washer rings instead of chrome ones.
These Schallers are smaller than the Schallers that are stock on some of my latter-year Rics.
If they're the smaller kind on the guitar you want to buy, you can get some Gotoh Kluson look-a-likes and they'll be a direct replacement. I can't tell by looking at them, though.
The old Klusons ("vintage") had a definite working life. Newer Klusons and K-clones (especially the Gotohs) are better-made, smoother, and more reliable. I typically swap out incorrect tuners. There's nothing uglier than a holey headstock, Batman!