Hi, I have a beagle that was raised with rabbits and she would never harm them in any way. And I also have a beagle basset cross that I rescued at the age of 3 and I have no problem with him and my rabbits, I have three of them. I think its best if you find a dog that has a history with other small animals and only let them together when you are around for the fist while. You can try having the rabbits in a cage in the middle of the room and see what the dog thinks of them first, if he doesn't bother with them, let the rabbits out and keep an eye on them for a while, I would NEVER leave them together in the same room if you are not at home even if you think the dog would never hurt them, you just never know what could happen :0)
Good Luck in finding your dog!