A thin needle-type file is one handy tool. If you get yourself a FB planing and a new bridge, I'd recommend getting a slightly high-ish cut, as some luthiers do seem to think that as long as it doesn't rattle, the string should be as low as possible. With one of these, it's a piece of cake to file off some excess wood. (But some carefulness is advised, as wood can be filed away but not put back!) If you think you have filed them too far into the bridge, any luthier will be able to file down the bridge until your strings rest as deep down in the grooves as you want 'em. You could even do this yourself if you're not afraid of a displaced sound post of misplaced bridge - I sure as hell wouldn't, but that's just me. You'll also become every other student's best friend, as you're hardly the only one with setup issues!
Anyways, if you think you couldn't handle higher strings for solo playing in thumb position, you MAY have a slightly too concave fingerboard. I played this one bass that had been set up by a violin specialized luthier. You couldn't play it as the vertical shape of the FB made each string rise very steeply. And yet you couldn't file down the bridge, because then the strings would rattle against the end of the FB. Consequently, the string height at the en of the FB was very (too) low but at the highest spot, I'm not joking when I say it was at least 15mm even on the G. If you have noticed even the slightest tendency towards this, a planing is indeed to be considered. It sounds strange that there should be no good bass guy in the area. Where does Joel Q repair his instruments, for instance? Send him a mail, for all I know. I think you can do that if you click on his profile.
Oh, and! Congrats on the successful audition! It was your first, right?
