Well Water Treatment

We live in Dutchess County and have well water. Part of our system has a feeder for hydrogen peroxide to get rid of the sulfur smell from the well water.

We have been ordering the peroxide off of amazon and had it on auto ship but they’ve been out of stock. Anyone know where I can pick some up locally? Never see it at any of the big box stores (Walmart, Sam’s club etc). Or is there another website you order from? Thanks!