I've had great luck with 123 SST and killed a nice chunky doe at 200 yards this winter with it. They've been kind of a pain to find lately. They make a 123 ELD-m that supposed to be designed for the Grendel that might work well on deer and antelope sized critters.
I need to check but I might have some Hornady brass. I'll shoot you a PM if I find a usable amount