I can't directly speak from experience with games with power supply "boards" (or linear power supplies vs. the switching units I'm used to with JAMMA games) but about the only event where any power supply would destroy a game board is if the +5 voltage goes extremely high, and I can't see that happening with a linear unit.
if anything, your situation would merely involve the +5 not being high enough to power the game board, and you'll just be looking at a blank screen.
I don't know if you can just rebuild yours or if you want to go the route of just replacing the whole thing. but I think you should be fine.
believe me, from the old days when my family had their arcade, I never saw a game where even if the switcher died that it took out the game board. and now, in my journeys as a tech in our new arcade, the worst case scenario I've seen was maybe the power supply's +5 skyrocketed to like 5.6V, but none of the games were ever damaged by this. switchers I have found you can get extra life out of them just by cleaning the +5 adjustment pot, or in other cases they were just bad and I had to replace them with new ones. they still fire up every day.
good luck, and I would maybe check Bob Roberts for a rebuild kit, unless it's very bad. I can't see these being that difficult to fix... caps, and maybe some transistors. transistors will be the most difficult part, and that's only cause you have to throw some thermal grease on them.
