Honestly I wouldn't be looking at alternatives to get his art if he made it accessible for purchase and not whatever archaic bullshit he is doing now to sell artpacks. When I messaged him, I genuinely had some disposable income to throw around at the time, and I honestly did feel bad that he was getting unjustly punished by Gumroad for the people doing chargebacks. So figured, since I have searched high and low for leaks and frankly got tired trying to find the sets I wanted, I'd just go straight to the source and throw him some dosh for a couple of packs and be a happy camper. However, I have been waiting over 9 months to get a response, and frankly I cannot be asked to wait any longer (disposable income got spent on other things since I gave it like a month to get some sort of response before I used it). I didn't want to be "that guy" and spam his inbox every single day, but that might be the only way to even reach him if he even bothers to respond at all. His patreon was the same deal for the brief time I was subbed. I messaged him there about an artpack I had missed and wanted to get, only to get an answer through a reply to a comment left by someone else on one of his patreon posts with not a word straight to me.
Love the dude's art and I get that we are all human, but like jesus christ. Hire an associate or something to check your damn DMs if you are too busy to get back to them.