Quarantine doesn't do any good after the fact. Sure, you can go ahead and move her, but there's no guarantee you caught things in time. Be glad it's just a possible RI and not IBD.

Definitely get her to a vet, an RI is nothing to mess around with. No idea what it might cost you, since it varies so widely with vets across the country and also depends a bit on your relationship with your vet. I usually get in and out at mine for about twenty bucks, but I've known her for years and she sees all my animals.

Good luck.