I have purchased it at Specs and Liquid Town in Corpus Christi, Texas. Specs is about $25. Specs is a very large retailer, and I expect if you are in Texas, near a Specs, call one and check - can probably get it if they don't have it in stock. I think Liquid town is more of a local Corpus business. Either one - plenty available. Not sure if they will ship.
The Party source in Newport, KY (across from Cincinnati) also carries it in limited quantities. price was about $30. They indicated they will ship to certain states, but the shipping charge seemed pretty steep to me.
I was interested if anyone knows of availability near the Palm Beach, FL area. Expect to be there in the future.