Solder for quick repair of snapped lug

High Force 44 is entirely different than any solder you've seen. A Gunsmith friend recommended it and demonstrated its strength by soldering the end of a copper cable to a chunk of iron scrap and beating it against an anvil like a hammer.
I agree that a pro can almost certainly do a better job. I was citing my experience with a particular type of solder since the subject came up.

I doubt I or he could make the repair invisible but it would be serviceable and unobtrusive in daily wear.

PS
Specs
"
28,000 PSI-Flows At 475\ F. The Best All-Round Solder For Gunsmithing
Brownells Hi-Force 44 Solder is an alloy solder containing 4% silver and 96% tin. Excellent for steel, stainless steel, nickel, brass and copper. Completely non-toxic. Flows free and smooth at about 475° F., greatly reducing heating time. No need for cumbersome oxyacetylene setups. Prevents black oxide formation to reduce cleanup time. Provides 14,000 to 28,000 PSI tensile strength. Will not crack under stress as do other low temperature soldering materials. And, a big plus . . . customers report that parts joined with Hi-Force 44 Solder showed no effects when immersed in hot bluing tanks! Use #4 Comet Flux. "

The flow temperature on that gunsmithing solder sounds interesting, but unless the OP has experience soldering at this scale, I can't see using a torch, and certainly nothing larger than a smith's little torch with the smallest aperture tip. Huge risk of overheating everything here.

If this case was made of a noble metal, lasering is 100% the way to go. No clue if a laser weld would work on copper alloys, or if you'd find a bench jeweler willing to try it. But researching that first is how I'd proceed.

Post-procedure pics please! 😀

Thank you everyone for your responses.

I will put this project on the to do list over the next couple of months.

Of course I will update as it progresses.

Here’s a pic of the dial and movement for those that are interested, a subtle but beautiful dial and well worth the effort to bring back to life!