Sorry to hear about your father. Hope you’re doing well.
You could also buy an upper that isn’t PSA, if desired. Doesn’t have to be PSA, necessarily, but if you click that affiliate marketing link disguised as a regular one, someone will get credit for the sale via tracking cookies.
What would you like this rifle to do? If a PSA upper fits, and I think it would, then so would any other brand AR upper in .223/5.56, 6.5 Grendel, 350 Legend, .300 BLK, .30 Hamr, etc. But a PSA upper may do exactly what you need, also.