Presumably you have googled RAF Llanbedr 1948/9? If not, I think you might find some more information. The RAF Mountain Rescue Team used to be based there until late 1949 when it was transferred to RAF Valley, where I used to be based, maybe google RAF Mountain Rescue for info?
it was indeed welshyorkie, when we married my hubby was a party leader at RAF St Athan MRT and they used to do exercises and on a few occasions call outs with valley