Surely there are more than two vets in your entire region?  Ask around and
find another vet for this.  Without knowing the cause of the sores, you could
make things worse or mask real problems.

Angela,

I hope you can find another vet. Is there anyone else within driving
distance at all? It would be worth it to your guy for you to extend a
big effort to get him in sooner than 2 weeks.

Your cat sounds very uncomfortable. He's probably grooming himself
constantly because he itches. It could be an allergy, or a fungal
infection like ringworm, or something else. If it is a fungal infection,
you could also get it.

I would not use peroxide unless the sores are dirty or infected.
Peroxide is a good cleaner but it eats away the good and the bad tissue.
It will not let a scab form if you use is every day. Baking soda would
probably really hurt -- being salty. I don't know if that would help
your cat or not, he needs a vet's advice.

The food you're using is relatively new, your cat started getting sores
after only 7 months on it. He could have developed an allergy in that
time. If you can't get to the vet immediately, you might try switching
over to a novel protein food (one protein, one starch, few "extra"
ingredients.) I believe you have to have a vet prescription for them,
though. You could possible try a good-quality natural food without
chemicals, etc?

Let us know what happens, I hope your cat can get some relief soon.

Rhonda