Joe,
As far as I know, it is no longer available under that brand name, at least in hobby in hobby shops. However, if you have a plastics distributor or supplier near you (plexiglass, lucite etc), check with them and see if they can get you a product named Pleximent (Methylene Chloride). It's the commercial name for Weld-On #3. Unfortunatly the smallest amount you can purchase is probably a quart. My dealer used to supply it in quarts for 4.95 a quart (the last time I bought some was 3 years ago). Was checking a couple of weeks ago and was informed he would only supply it in gallons now ($26.95 a gal). I figure with care that's a ten year supply.
And by the way, welcome back to the hobby and to the forum