here you go, it is from s7 edge Telstra (AUS) Nougat firmware. I think it should work with Oreo too. I am still on nougat as I did not feel like flashing black the original CSC to get the Oreo OTA.
It's interesting, it's nearly double the size of the Tmo one. Did it install easily? I'm doubtful a Telstra Australian CSC will give us wifi calling on tmobile. Maybe we just need a different tmobile CSC.