If your dog is insured the insurance should cover the cost of the hernia repair.
Do you have a SPAYWATCH near you, we have and they help towards the cost of neutering any animal if you are on benefits?
Other than that i am sorry but i can't help you. Maybe a loan from a friend that you could pay back in installments??
http://www.yell.com/listings/DoFindL...fare-Societies