For emergencies all I can think of is Tufts Foster in Grafton which wouldn't be too far from you--30 minutes.
I don't know if there are recommended vets that work in that hospital and they are probably one of the most expensive places around you (at least they were when I have been there years ago in emergency situations). Other than that, I live in western MA (south hadley). My vet is probably an hour from you taking the pike. There's an e-vet in springfield as well but I've never gone.
Sorry, I used to live by you and will again soon but for now I only know of Tufts since I only need an e-vet when I go home to visit there.
Did a quick VCA search. There's an exotic vet in Worcester and one in W Brookfield Have never been to them, so I can't say they are good or bad. Maybe if you call and talk to one of the vets or go in and interview them, it would give you a better idea. Or maybe someone else from the area can chime in with personal recommendations. Sorry I don't have any but I wanted to give you the Tufts link in case you were in an emergency situation and needed to find a place open. And the VCA links are just me throwing out ideas for regular vets. Good luck.