I think for the most part when it comes to valves, they seem to be universal....most parts houses are carrying one size fits all valves....
I did a switch out with the first SQ, I needed to borrow a valve off the SQ temporarily, to use on a Maytag.....
when I got the parts store, and purchased a new one for the Maytag, it was the same one that came off the SQ...identical in every way, so I stuck the new one on the SQ.....but had to drill it out first...
I don't see why a regular valve from an older machine would not fit, check for any restrictors, and as long as the mounting holes match up....you should not have a problem
I know GE filterflo have a restrictor for water flow, not temperature control, again, easy to remove, but you have to take it apart to get it out......and my solidtub SQ have a restrictor, but again, for the time fill water flow...
I remember a few 60's Whirlpool valves having a removable restrictor disc on the COLD water side, behind the screen, simple to remove.......funny how times have changed from a really WARM wash, to a really COOL wash