They are still on amazon but you will need to buy the adapter for the snes classic separately. Here is the link: https://www.amazon.com/8Bitdo-SN30-Wireless-Gamepad-Original-nintendo/dp/B08536VCZL
Edit: here is the link for the adapter you will need, as the 8bitdo snes classic adapter won't work.
sorry you got bum controllers, but my SNESC controllers feel great all-around. You might want to consider using one of these adapters to grab an OG SNES pad. I have one and it works as advertised (i use it with a Super Famicom controller + extension cable) -- https://www.amazon.com/Hyperkin-Controller-Adapter-Classic-super-nintendo/dp/B075RMYMNH
I just went through this. It doesn't look like 8bitdo offers this option anymore because you can't buy the SNES classic in stores since 2019. If you love their controllers as much as I do... here's how I solved it:
https://www.amazon.com/gp/product/B075RMYMNH/ - Hyperkin SNES to SNES Classic adapter
https://www.amazon.com/8Bitdo-SN30-Wireless-Gamepad-Original-nintendo/dp/B08536VCZL - 2.4ghz SNES wireless gamepad
Having the original SNES controller form factor (no analog sticks) was my top issue - and it works great. It's just less clean with a 6inch adapter sticking out of the SNES Classic.