Since she is only 5 months old, you don't need to get her spayed right away. I got my Amelia spayed when she was 13 months old and she did fine. If you can, save up money as you can over the next few months. Decide on which vet you want to use and make what they charge your goal. Ask about the exam cost and the cost of pain medication since these tend to be extras they don't tell you about when you call. I would also plan for a bit more, maybe $20-40 just in case you need a bit extra.
You and your kids can try doing some work in the neighbourhood. Shovel walks with it snows, hang lights if you can and other things, use this money for the spay fund. You can also try selling some stuff you don't need. Since Christmas is coming, you could ask fro money instead of other gifts, it can at least help.
Some rescues have deals with vets for lower cost spays and neuters. You still have to pay some, but it is less that what you would normally pay. You have to contact rescues in your area to see if they can help. You should make sure the vet they use is rabbit savvy. You can get cheaper vets, but they aren't as good and it can be more risky.
