For my little bunny oreo

My name is Donna and I have a bunny that is really poorly that needs lots of medication due to having EC and a very bad deep inner ear infection and if he doesn't get no better without the medication he will have to be put to sleep.
I have rescued soo many rabbits in mylife but never seen anything like this and I'm scared to lose him I have already paid alot out and now I'm very low on money to save my little bunny and I'm asking for help which I've not done before.
PLEASE HELP ME TO SAVE MY BUNNY