Does fort mountain state park have a store for campers to buy supplies?

There are some supplies, but they're mostly small, last minute things. You should come prepared to the best of your ability. Chatsworth is also a short, 10 minute drive, down the mountain. You can find many more supplies there.

Get most of the supplies beforehand. There is a shop with very limited supplies.

I would stop in Chatsworth if I knew I needed a few things before I went drove up the mountain.. Especially of you are in a motorhome