There s a pet shop off 87 exit 14 in the shopping center that has all kinds of turtles including babies. very knowledgable. I don't know the name of the store.
I know you said Westchester but if your ever on SI I have a bunch of red ears and small painted turtles at the pet store I work for and I could hook you up, PM me . And a little FYI it is against Federal law to sell ANY turtle which shell is under 4 inches due to salmonella.
Not westchester but pretty close Pet pantry warehouse in greenwich CT had a 2 of them about two months ago. If interested give them a call first to make sure they still have one.
From what I always heard it was that you weren't supposed to buy them in chinatown because they fed them raw chop meat and that's why they were afraid of people getting salmonella. I always had tons of baby turtles as a kid I caught in the lake by my parent's house and I never got sick or had any issues. My bathtub ended up being a turtle tank at one point. (we had a stall shower and never used the tub so I put it to good use LOL)