Those pics of 'your' wonderful battered tom reminds me of a few lines of poetry. It's from 'Esther's Tomcat' by Ted Hughes:
Daylong this tomcat lies stretched flat
As an old rough mat, no mouth and no eyes.
Continual wars and wives are what
Have tattered his ears and battered his head.
He's gorgeous. So much character. And he needs love.
Don't put too much info about him in the notes and be very wary if anyone calls claiming to be his owner; they may not be telling the truth. It's a good idea to keep some info back so that they have to tell you something which definitely identifies him as theirs.
On the other hand, if you do find the owner, do they deserve him?
imo he's better off with you and hubby.