... (the finials are exquisite - I wish Walter could offer these separately to apply to all my other signal masts) ...
Ask them. Walter and Debbie have mixed and matched signal castings for me when I needed a mix of SA parts for UP prototypes that happened to be a hybrid of their normal sets.
Two things surprised me about the semaphore kits. First was the solid PB mast. Lack of an easy wire conduit precludes illumination. Possibly the loss of Special Shapes fine brass 0.032" tubing is a factor here. I would simply substitute ngineering.com SS tubing, which I do already for the Showcase SA kits. The second head-scratcher were their somewhat obtuse recommendations for color lenses in the spectacle - Tamiya transparent colors are absolutely the go-to here.
Anyway, yes, excellent kit, well-executed and characteristic of Walter's attention to detail. Added benefit is it saves me from having to get into producing semaphore etchings.

Main thing I would add is if semaphores were on my short list would be to reproduce the head in 3D resin (like I did with the SA) for easier illumination, and ...possibly... find a way to run a pushrod up the mast for actuation. But that's me.