I know this is a couple weeks old at this point and I hope you were able to get some care for your bun at the time. It is the worst feeling when you need help and can't get it. There are not many vets who actually know rabbits where I live, so I'm all to familiar.

Not sure if your vet would do this, but we got some metacam in oral syringes, along with an IV bag of fluids plus the needles to administer them. It is awful having to give the little taffers a needle, but this combo has helped them through stasis and minor dental issues when no vet was available here. I am not sure if there are other parts to treatment for your bun, but I assume painkillers and fluids are part of it.

I'm in Canada, not sure if that makes a difference with the availability or legality.