Congrats! You're finding out how much fun it can be to play some of these grand old horns. The 'LP' stands for low pitch, which means that the horn can play in either Bb or A. I always get mixed up as to which pitch is 'low'--I think it's Bb, but if you have a horn to compare it too you can find out really quick.
I'm curious as to if the horn is really heavy and/or clunky feeling. A pawn shop near me has a Buescher True Tone cornet made for the military bands in WW2. It's very heavy, clunky feeling and I think it's real hard to blow. The horn scared me off of bidding on a couple of old Bueschers. Then, I heard that the military horns were made to different specs and were supposed to be heavier. What is your horn like?
Anyway, it sounds like you have a fine horn and a really good candidate for a trip to England to Leighs shop for a stunning restoration!
