I'd take him now to whichever vet you feel will do a proper examination of Sooty, and worry about the cost later
chances are when your own vet calls you will still not feel happy that he is receiving the best care
I am in West Wales, and I too only have a rural vet, who is mainly farm animals - that means they are out and about regularly and on 24/7 call, which without a car is reassuring for emergencies, but I also have insurance so I can go to a more specialised small animal vet if necessary