Plenty of RIBs use Beadnell
Beadnell - about two miles south of Seahouses, is a big launch site for RIBs. Mostly for divers visiting the Farne Islands. The barrier is open Easter to the end of October, and on summer weekends it can get very very busy. There's a tractor service for launching via the beach.
I've also seen quite a few launching from Seahouses itself. I think this also has 'seasonal' opening hours.
Twenty years in the aircraft industry, five years boating, and I still can't spell propellor ...