Dilemma day!

It's been a dog day! And it's not me! I met this fellow this morning wandering around the church looking for a friend. When all the parishioners had left, there was only me as his last hope! He looked hungry and tired. So I have cared for him today - but no one has come looking for him. I think he has been abandoned with a while. He is a friendly Jack Russell terrier.
But he has been in a good home once, and he remembers because he is no trouble. He is quiet affectionate. He went with me in the car to the vet where I had him scanned for a microchip - but no joy.
I would like to treat him to a better life than he has had in recent days but I know it wouldn't work out. He would be alone a lot and that wouldn't be fair.
So, if you know anyone who might like to have this pal at their home, please let me know.