Hmmm, if all four of these platforms are blocked/restricted, then it's unlikely that another site wouldn't be. I think there are two options:
Option 1 would be for you to use a payment intermediary service where you can pay a platform to make the purchase for you.
Option 2 would be crypto. Seeing as you are able to use the site and leave comments, I am guessing you can also access and download games, and you are only having issues with the actual payment part of it. If that's the case, then you can send me the crypto, and I can send you a redeemable key that you can use here on Itch.io. I haven't done that previously, but if that works for you then we can try that.