I bought my latex on ebay for somewhere around 35 us google mask latex and you'll see a few companys that sell it.they won't ship to me in the winter though afiad of frezing but in warm area prob ship year around.and glue guns seem to be all the same just look at the wattage; 80 watts is good.
Another forum poster turned us on to the stuff you can buy at craft stores like Michaels. Its called "Mold Maker" from a company called Castin Craft. You can probably buy it online. We used it on a bucky skull and it worked great.
The stuff is pretty thick but we tried several methods out on the skull so it ended up with a few layers which was plenty. First we stretched a panty hose over the skull head and then sliced the panty hose in a few places to give it the "hanging flesh" look and then coated most of it with one layer of the mold maker. Then we put a thin layer of the stuff on our granite counter top and let it dry - then rolled it up to form some "dangly" stuff and stretched that over the skull as well. After that we dipped some cotton balls in the latex and threw then on as well. Here's a pic of the skull somewhere in the process before we put any of the stain on. It doesn't look that great in this picture but when we were all done it looked great. View attachment 3438