Ferro Frit 3134
Ferro Frit 3195
Silica (325 mesh)
Gillespie Borate (or Gertsley borate)
Kona F-4 Feldspar
OM4 (Kentucky ball clay)
If you're willing to do some basic reformulation, you can shorten this list further. I'd get rid of the Wollastonite since you've got Whiting and Silica (Flint). You can find plenty of good glazes without Spodumene. I'd go with Frit 3110 instead of 3195, maybe add some 3124, too. But honestly you can probably get by with just 3134 to start. Definitely use Gillespie instead of Gerstley- it's way more consistent. Ditch the Ball Clay, EPK will cover it. But get some Bentonite (just a couple pounds- you'll only need 2-3% per batch). I tend to use Nepheline Syenite way more than Kona. For colorants, get Cobalt Carbonate, Iron Oxide, Copper Carbonate, Chrome Oxide and Rutile, or just use Mason stains.
Just find 3 or 4 good recipes and color them the way you want. Then you can really narrow down your materials inventory.
I agree, you can get by with just 3134 as your frit, leave out wollastonite (sub w/whiting & silica), and I also got neph sy, you can make a sub for kona with it as well - you'll have to reformulate for both of these, but it's not that difficult. In most cases you can exchange 3134 for Gerstley Borate, but I have and use both, your budget can decide for you if you can do both. I did get some ball clay, it's pretty cheap. Spodumene can be a "wait" item too, because even a basic pantry can run you a pretty big invoice. Look at quantity pricing, when I bought my glaze pantry ingredients last year it was cheaper in a lot of instances to get 50 lbs rather than 10 (if you are at a supplier, not shipping). Like 10 lbs of OM4 was like $15 or $16, and 50 lbs was $17.50. You might want some alumina hydrate for kiln wash, but with electric I got by with silica and a mix of EPK and calcined EPK until I could pick up a few pounds. I calcined my own in a bisque firing, just fired a previously bisqued bowl full of EPK. You'll need colorants, they are expensive, but a necessity. If you want to cut one, you can maybe do without the chrome to start with, but I'd spring for the cobalt carb, iron oxide, copper carb, and rutile for sure. You'll need an opacifier of some sort too like zircopax. It kind of stinks for half your bill to fit in a brown paper bag (colorants), and the other half get loaded at the dock, such is life. So here's my bare bones list:
The ones with the star I went for 50 lbs, it was way cheaper. Add in whatever else you can afford, but you can build a lot with these. Once you've worked with some recipes (keep testing, try different colorants with bases), you can expand a lot and add different items as you make it to town. I live about an hour away from my supplier, but they are only open weekdays, which is when I work, so the days I'm off to drive over while they're open are few, just keep a running "grocery/wish list". Good luck, just go for it, you'll always have a list of what you'll need to try that other crazy recipe you saw on that site....