I think it's not bad thing that BitPay don't work in your country . From my experiebce their service is really shitty.
There is good advices above given. BTCPayServer is great decentralized option, but you would need to run a node to use it. Coingate and Coinpayments csn be a good option, but I don't know, do they operate in your country.
BTW, why stablecoin? Fiat wouldn't be better option?