From a quick look at other 10" drivers, only Faital-Pro seem to offer a 4 Ohm variant.
I checked out another 4 drivers in total; the Pulse 10, a Fane Sovereign 10-300-2, a Beyma 10 300WRS and the 4 ohm Faital-Pro 10 PR 310. None as 2x10's are drop-in good matches to a 100L cab in respect of an indication of "heavy breathing", requiring 3 ports to control very high rear port air velocity.
If that extra work is something the OP can consider, then the Fane or the Beyma are probably the best balanced.
The Fane is £77.0 from Blue Aran. The Beyma 10 300WRS is £75.0.
Other contributors may assess my comments about the high rear port velocity and decide whether that alone is or is not a deal breaker.