The only "Super" .303-25 packets I have here are the red and yellow ones that say "Super Cartridge Co, Melbourne", on the end flap. The original brass was Boxer-primed and loaded with the "Super" 87gn soft point bullet. There are a few "Riverbrand' packets somewhere, as well, but these contained re-formed .303 Mk7 cases that had been fitted with brass-cupped primers, probably RWS 6000.
I got a motley bunch of packets and ammo / fired brass, when I bought a Lithgow-converted, "Sportco" SMLE conversion, about twenty-five years ago. .303-25 kills the ferals just as dead as anything else in the cupboard.
It is my "usual" field hunting rifle, but I use re-formed "modern" cases for "polite" hunting. For "rough" culling, often from a dirt-bike, where I don't expect to find much of my brass, I use reformed, once-fired Berdan-primed .303 brass. The slow, 1:14" twist barrel will only work with "short" bullets, like the old Supers. Slinky, 90gn BT HPs will not stabilise in that twist, at safe velocities.
The “Black Label” “Super” packets are new to me. Nice find.