Perhaps it's just the way you phrase it but I get the impression you may not have given this as much thought as you should.
I'm presuming your rabbit is a pet as you're only looking for a 'dwarf breed' rather than any thing in particular. There are also the heath issues to her and the male you borrow. Rabbits get STDs too! A random male could bring all sorts of diseases.
Do you know the risks that pregnancy carries for the mother? Rabbits get all the complications humans do but without the health care. Death or an emergency caesarian are real possibilities that need planning for. You also need the mental strength to be willing to hand feed babies every few hours for weeks or cope with clearing up the half eaten ones if the mum doesn't take to mother hood.
Can I ask what you know about your rabbits genetics? Are there any medical issues in her parents or grandparents lines that should be considered when picking a mate? She could be carrying genes for bad teeth without showing any signs herself. Mate her with a male carrying the wrong genes but also symptom free and you have half a dozen unhomeable babies with short life expectancies and expensive re-occurring dental problems.
If you've planned for all of the above, sorry for the lecture. Asking for a random male is not really the best option for breeding though. Presuming you do know the genetic history of your female (if you don't then don't bred from her), the best option would be to go back to the breeder and ask them for advice. They'll be able to recommend the best line of males to breed her with and probably supply one.
Tamsin