Just buy their physical books, digital editions, and merch. That's giving them money and driving up their sales and attracts more business when they go to license a product and can show they their books sell. More sales = more content in the future. They really don't need a free donation, you're better using that money on a charity if you insist of giving away money.
Essentially you're donating money to an actual business which seems weird unless they actually put add a go fund me page because something happened. So buy a book, subscribe to the magazine, get a figure, buy skateboard, buy a shirt. Hell you can buy the gift certificates and give them to your friends or online people or random degenerates on the forum.