BS”D
itzik, shwekey’s “al homotayich” has an arabic twist to it. that’s not authentic either.
It is the closest popular and easy to find example of proper Sephardi havara as spoken in the US Sefardi communities. Sadly, the Greek communities in the US have been absorbed into other Sefardi communities and I don’t know what they preserved. Maybe Etz Ahaim in NJ or the communities in Seattle have websites where you could hear their nusach hatefila.
Try also the Ahava veAhba website (Egyptian community) if it is still up but most of the piyutim and shiurim there are recorded by the rav (R’ Shimon Hai Alouf) who was born in E”Y or by older men who were actually born in Egypt.
I can’t remember how Rav Nissim Yagen ZYA spoke on his tapes; I only remember that the one I listened to was very easy for me to understand.