Not to spoil the fun, ya I'm sure Dave is getting more forgetful, after many years of alcohol based AF. ANYWHO...I always got my Prestone RV AF at Walmart, and yes, they now have sta-bil as a replacement. My wife went to Prestone's web site, and it said Advance Auto carries it. I said they would not have the RV stuff, but she called anyway. Yup, they had 8 gals of Prestone RV.
It is good RV anti-freeze, and really works well to lube all the seals. I add just enough to my Black tank to not let it dry up, and my BT valve works super easy in the Spring.
Jerry