Unless i am mistaking only the LMC or Lee Metford carbine had brass crews.
So if you have an ''E'' stamped on top of the barrel, steel screws should be used.
That being said i did find a place that makes repro brass butt plate screws, not cheap but again probably the only option out there.
They are for the Martini Henry rifles but should still fit.
Again i'm not sure if i can post outside links here so if you still wish to fit some, just let me know and i'll provide you with the link.
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