On the one occasion when I approached a rescue group, I ran into the same problem. I'd just lost my male IW, and my unspayed female was pining mightily. Breeder didn't have a litter planned for that year, so it would have been close to an 18 month wait. So, I briefly listened to some friends and reached out to a local rescue. My goal was to find a youngish dog or puppy (of any breed or mix) whose temperament and build would be a good fit.
Found one at a local rescue. Filled out the application (including references).... and suddenly ran head on into their "policy" not to adopt (hate that word) to a family that had an unneutered dog on the premises. If I was willing to spay my female, they'd be willing to let me have the pup. Un huh. I pointed out two issues: First, nowhere on their website or application was the policy either implied or spelled out. So, did they have it in writing anywhere? Umm, no. Well, that being the case, why was I being held to a policy that wasn't documented anywhere?
The second issue that I pointed out was that I had a longstanding relationship with the breeder from whom I'd purchased my female IW. (Ironically, the breeder had given me a glowing, written recommendation). I also pointed out that the female was show quality, had been shown and that I'd agreed, in writing, with the breeder not to spay the female unless there were pressing health concerns. I also pointed out that were I to spay the dog, I would be unable to show her per my agreement with the breeder. I also asked them to consider the implications of my willingness to violate a signed agreement (with the breeder) in order to comply with an undocumented policy that they claimed to have. If I was willing to do how could they trust that I would provide even minimal care to their dog? I certainly wouldn't trust them were the roles reversed. Finally, I pointed out that, unless they fervently believed in immaculate conception, there would be no 'accidents;' their pup was already neutered.
The sheer irrationality of the whole exchange annoyed me so much that I promptly withdrew my application and left. Later, I found a scruffy, well-built puppy at the local shelter who adored my female (as she adored him).
A final note. The dog that I was initially interested in stayed at the rescue facility for another 9 months before he was removed from their adoptions page...