What's Standard Here??

[THEE_LIONN]

I won a seat into the 100k pro-bounty on AP.
Buyin is 1k, and I'm in it for $100 of my own money.
It's all well except I'm mostly a cash game player and not very confident going to the MTT. Someone from my home game wants to buy a piece of me. So if he puts up $500 do I give him 50% of winnings? If not what's standard for this kind of thing.
(I posted this in MTT, but obv no responses at this time of day)