Russell,
The lock clip will certainly work, though might require a some drilling or filing at the small end. The thread on the screw will be different, however, as the New Standard is Imperial thread whilst the thread of the screw above is for the German built horns which are Metric. HOWEVER, I am certain that a good repair shop can either find a screw or tap your horn for Metric. I'd buy the parts and if it doesn't just work, have your shop fix the screw issue for you.
Doug
Sterling Virtuoso 1065HGS & Adams E3 Prototype 0.70 Top Sprung valves
Sterling Virtuoso 1050HGS baritone
New England Brass Band
Winchendon Winds/Townsend Military Band
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