I don't buy wires, I get scrapped alluminum wires and anneal them...
I have two plastic bonsai pots, just because it was on sale, it's for low budget trees, good trees deserve good pots...
Expanded clay pellets doesn't have much use for Bonsai, maybe for training pots it can be used on top to keep humidity or insulate the roots...
So nothing that you actually need to buy, instead of wires if you can't get them for free...