RevKJC,
I do not know what repairs it needs besides a good cleaning, but be aware that because the valve slides do not pull out, if anything needs serious work, there may be a high liklihood of the horn needing to be disassembled at the solder joints to get to dents in tubing and to effectively clean the 1-2-3 tubing. Also, make sure you check to find out whether it is high pitch or not before you dissassemble it as that has a huge impact on its playability.
Doug
Adams E3 0.60 Sterling bell - Prototype top sprung valves
Concord Band
Winchendon Winds
Townsend Military Band