I ended up ordering a complete BCA upper. The would-be donor upper shoots well: ~1-1/4" @ 100 yards, so I didn't want to bugger it up. I'll borrow the optic off my 444 Marlin for the time being. I'll get a few boxes of factory ammo for the time being as well. The key takeaway for myself, it's not a SHTF rifle, so don't stockpile the ammo for it, like it is. Ditto w. reloading; if the ammo is relatively inexpensive, don't go hog wild loading / shooting it. .223 makes paper holes for less $$$. As the kids get older, I can get them .350 uppers as well, and we can share the hunting ammo supply. If I like it, the 444 Marlin may get moved on. Ditto for the .44 Mag single shot. $250 upper Recycle optic (1) magazine $20 Factory ammo (2 boxes for now) $40 Possibly sell 444 Marlin for $200-$225 would recoup most of it.