Gunbroker has a couple ads with .32-40 brass. Getcha some🤑
Quality Cartridge sells new .32-40 brass. 20 empties cost $45 plus shipping.
Graf & Sons sells the Quality Cartridge virgin brass for the same price, but you’ll probably find it out of stock. If you hit their Notify button, they’ll let you know when they get some.
Quality used to be in Maryland. Might call them and get lucky.