I don't think you would find anyone in this area looking for a foster owner. When we have had them apply to the RSPCA we would do a home check and thoroughly check their knowledge and what they wanted to do. Their set up would have to equal the requirements me ask for (unless there was a specific reason for the rabbit to be in smaller accom.). The foster owner has to be 18 and also able to get to their vets.
When I fostered for Kris it was pretty different from what I think both of us had had before in terms of rescue and foster carer, but that was an extreme situation where Kris was desperate for help (because my accom. was too small, and also I lived a long way away from her vets).