Ok so just in case anyone stumbles across this later via the Google machine or something, I ended up going with the tank exchange option at the Homebrew Emporium in Rensselaer, which is pretty close by.
Thanks! I called Oliver's and Carbonic and they said no as far as beer gas refills, but I'll give Westmere a go when I finally empty this thing. Sipping a nitro poured vanilla porter as I type
I mistook beer gas for plain co2 so I'm not sure if Westmere does beer gas or only co2. But the guys at homebrew emporium are great I get all my grain from them and the tank exchange is pretty convenient.