I didn't check out either of the live poultry places in Astoria, but I ducked into a number of butchers to inquire. International Meat Market on 30th Ave., an all-around excellent butcher, didn't have squab, but said they could get it with a few days' notice. They also had a number of other unusual poultry, such as poussin, pheasant, and goose.
Try the live poultry houses in your hood. I know there are several in Astoria, but don't have details.
I go to Bismillah in Woodside since it's within walking distance. They have pigeon, assuming that's what you mean by squab. Call first.
Bismillah Live Poultry
37-15 55th St, Queens, NY 11377
re: Joe MacBu
Squab is baby pigeon.....adult pigeon is too tough to use for anything other than soup. Even squab can be tough from the wrong source...I bought some squab from that locavore butcher in the chelsea market....as tiny as they were, they were inedibly tough. I was told later that they were "free range".