Assuming a 5 degree landing attitude, some 737 classics will smack parts on the ground at around 10.5 degrees bank.
I think the margins are better than that.
The following graph gives bank angle for x-wind 30 kt. If we take 140 kts approach, leaving 3 degrees of residual crab, and not fully banking by two degrees,** you only need six degrees of roll to cope with a 30 kt x-wind. And the 737-700 gives a very generous 14 degrees of roll before the flap track or (unlikely) the nacelle touches. And surprisingly, the -800 gives a degree more roll ability, because the approach speeds are higher.
(** The last thing you want is to be slipping into the upwind wheel, as that will result in an alarming gear-twang. Much better to allow a very slight drift downwind, and let the gear touch in 'trailing link' style. So slightly less than full roll is always desirable.)
