Chirp, there are very few rabbit vets in the US that actually know what they're doing and you will be looking at spending $100+ to spay your rabbit. Further more, while spaying MAY help, because she's an older rabbit the risk of complications for the surgery are increased and the chance of it actually doing anything have gone down.
Unfortunately this is just one of the facts of pet ownership and it is why many cats end up being strays and creating invasive feral populations that destroy native wildlife and have become a nuisance. People don't want to get them spayed and then their cats get hormonal and start spraying and they get dropped off in the woods somewhere to die of FIV or something.

The same with rabbits. Can't find a vet to spay, then they start behaving like a normal teenage rabbit, then the rabbit goes outside to get ripped up by a fox or something...
You may be able to locate someone by inquiring with house rabbit societies and house rabbit websites. I don't like their opinions on rabbit care but they do have lists of rabbit savvy vets online. if you care to ASK for a rabbit savvy vet from those groups, be warned they may tell you about what a horrible owner you are for not having her spayed by now. They can be SUPER bonkers. You may have better luck with simply training your rabbit like a dog or chicken to behave properly.