Nice old stove set @DickM !
Duct tape on the rim of the cup too

You can see it gets some use hahaha
I still have the original cup and handle somewhere here, but I use a modern GSI Glacier cup which slips right over the top of the stove like the original.
Is the pump attachment simply for cold climate use? I've never had a problem priming the stove in the conventional manner where it pressurises the tank via heat, but then again the coldest I've used this stove is -5 degrees C (23 deg F). We just don't get proper cold here.
That original Sigg bottle is awesome.
I think Svea and Sigg might have run some joint products back in the day. I have a Sigg Tourist cookset which is designed to use with a Svea 123 stove.
Some more Svea 123R love -
In use with my old 1945-vintage British Army Pattern 44 Canteen and cup set
Priming the Svea 123R by lighting fuel poured into the "dimple". This heats the generator and pressurises the fuel tank.
Heating water in the back of the Shorty Forty. I use a 20mm ammo can to carry tools and spares and the lid makes a stable base for 40 Series Camp Cookery... well, not really "cookery" in this case. More like "water-boilery"?
The Svea 123R with cup and handle. The thing next to the tank is an old Primus stove pricker. I had a bunch of problems with the built-in pricker in the Svea 123R stove and ended up chewing the gears on it. The "R" designation means that when you finish using the stove and turn it off, you keep turning it off and a set of gears inside the generator lift an internal pricker which cleans the jet. Sounds super simple and reliable, but not for me. After having problems with it all jamming, I simply removed the whole pricker mechanism and manually prick the jet after use, thus turning my "123R" into an old-school "123" instead.