If they don't want to work with you, maybe you can ask all the perspective duck/chicken customers if they would by your duck(s) for you. Either it would work and you would get your duck(s) or you might irritate the staff so they would sell you one or two ducks.
Until you have some friends for her, if you can't be with her 100% of the time, give her a clean stuffed animal and/or an unbreakable mirror so she won't feel so alone.
X2 (Edit: oops, X3 i meant CountryGirl12 squeaked in while I was typing )
Metzer (and probably others) will send two ducks, but it costs about the same as if you were getting 6. They have I think a $35 minimum plus you have to purchase a heat pack with only 2 ducks. We got our last 2 that...