You might want to hold off on the round ball mold until you decide what size ball works best for you. In my own .62 fowler I use a .60 ball. Some guys like a .590.
Ball puller, patch puller, breech scraper, jag, probably an adaptor to match the threads on those accoutrements with the ramrod and range rod. A range rod is not really necessary but makes things a little easier at the firing range and when cleaning.
You also might want a pan brush, but I find it is not necessary since my finger, or a leaf, works well enough.
A vent pick can be made very simply by straightening out a paper clip. I've also made them by taking a short piece of 1/4 inch dowel and driving a tiny nail into the end of it. Cut off the head of the nail and file it into a dull point. Or, just take a stiff piece of thin wire and bend one end into a loop that will serve as a handle.
Of course you will need a powder measure. You will need an adjustable measure at least in the beginning in order to determine what amount of powder works best for you. Once you have settled on that, it is quite easy to make powder measures for that specific load out of antler, bone, river cane, wood, whatever.
I use a loading block to hold several patched round balls ready to load. Some people don't use them. Whatever. These are also very easy to make yourself.
My loading block hangs from a throng around my neck, but I keep all the other little accoutrements in a small leather bag that I sewed up myself. Also, a similar little bag for holding round balls. These two little bags, along with a small pair of pliers that I have ground down one handle end to make a screwdriver that doubles as a flintknapper (or you could just go with a real screwdriver), some lubed patch material, and a small folding knife all go into my shot pouch. (please don't call it a "possibles bag")
Before you go to the expense of buying a shot pouch you could use an army surplus medical kit bag, a gas mask bag, a bag you might find in a thrift store, or you can sew up a bag to your own design, as I have done.
I don't use a short starter, but many people do. They are also very easy to make yourself.
For me, making as much of my own equipment as possible is part of the fun of muzzleloading.
