Since your TSC is far away, you may want to pick up some Corid to have on hand or you can order it online. I give my chicks a plug of sod and dishpan of dirt from the run the first week so they can start building the gut and be exposed to pathogens in the soil - plus who doesn't love to watch week old chicks dust bathingI'm open to suggestions on what else to get. TSC is a drive from the house and I won't be able to make a quick trip if something gets forgotten. Items for common injury/illnesses would be most appreciated.

Your other first aid/emergency supplies are likely in your medicine cabinet already - triple antibiotic ointment, band aids/sports wrap for any spraddle or splay leg (I've never had that with shipped chicks), you can always make your own saline with salt and boiling water. There are a lot of common household products you can use to treat minor mishaps.
I don't know anything about the panel heaters so can't comment on that, but I agree with @lazy gardener a MHP system is the best. I will never use a heat lamp again.
It's exciting to get new chicks! Congratulations, relax and enjoy them they grow soooo fast. Don't overthink and over read you will drive yourself crazy.
