advice I once got
I'm new to this site-- was just checking the web about Devon Rex's and came across your ad. I'm getting a Devon shortly so that's why the interest. I feel for you!
My cat got lost after we moved a few years ago, and some great advice I received from a vet was to put a well-worn (slept-in?) shirt outside in the yard, in case he was within a few blocks but lost, it was possible that my cat would be able to follow the scent and know where home was. I'm not sure how accurate that is but after a few frantic days, and my slept in shirt hanging outside-- he appeared again! Looking scared and happy to see us.
I just wanted to share that because it worked for me.
I really hope you find your cat soon.