Hi, Neems!
I don't know the answer to your question about vaccination being required before spaying, but I might suggest this:
If you find that you do need to vaccinate first, and Ton Ton will enter another heat cycle before you can spay her, you might ask your vet to provide a birth control pill for this one cycle. I hadn't known such a thing existed until I read about it here in another thread. It's not good for the health of the cat to use it over the long term, but might be a solution to keep Ton Ton from getting pregnant again before you can spay her.
I wish you best of luck, and as always, many blessings for the help you give to the cats near you!
