Having a good supply of fresh yeast on hand is a big one for me. Otherwise, the online sellers are pretty good for most of the rest.
Thing to remember on yeast though is that you can start your own from the remaining yeast in commercial beer. So long as its bottle conditioned.
You can add me to the ping list. I worked at the nation’s largest wholesaler of wine and beer-making ingredients when I was a young man. I ended up running one their retail outlets in Ohio for awhile, but after months of taste-testing everyone’s concoctions, I joined the military to take a break from it.
I know all the ins and outs, having to make my own wine and beer in the store for sampling. Best ever was a German double Boch. Smoooooooootttthhhhh.