Flopped middle pair with gutshot but faced with a bet and a call.

[myfutureself]

This is from a live tournament (100 players approx.) so the information is my best guess.

Stacks
Hero (Button) : 2,500
Player 1 (SB): 10,000
Player 2 (BB): 8,000

Blinds: 100-200.

Reads: Both SB and BB have been active since the first level and I'm getting suspicious.

Hand
Dealt KQo. Folded to me. Limped on Button. Small blind calls, big blind checks.
Flop A K J Rainbow.
SB bets 300.
BB calls.
Hero ???.