I guess it depends what type of sous vide bags you mean, FoodSaver vs Ziplock vs the other common ones. I know the French Culinary Institute talked a little about what is in them in their vacuum post
, maybe that will help. They seemed to indicate they are polyethylene, though I'm not sure if that helps on the recycling front.
I'd try to find the closest "name brand" match to your sous vide bags and then call the recycling company / department in your area and ask about them, they'd probably be able to tell you.
I hope that helps some, plastic and recycling isn't a specialty for me!