This is based off the current squads, its slim pickings to be honest

Hennessey (WAL)

Christie (ROI)
J.Evans (NIR)
A.Williams (WAL)
Davies (WAL)

Allen (WAL)
Davies (NIR)

Bale (WAL)
Ramsey (WAL)
Phillips (SCO)

Vokes (WAL)

I make it 7 Welshmen, Hennessey is the only debatable Welsh inclusion IMO, only reason he's in is because there is nobody else playing at a higher level