Those are some great references, thanks!
So interesting that they would blacken the ordinary leather equipment and adapt it to the wide piper's dirk belts.
I suppose the equipment was probably issued buff, and it was up to the soldiers to pipeclay it white, or in the case of the pipers polish it black.
The only image of piper-in-khaki I had studied was this group of photos taken in the Boer War period of members of the Black Watch, widely used for post cards at the time.
In it you can see the piper wearing his ordinary Full Dress dirk, dirk belt, and crossbelt, which doesn't seem practical for campaign.
(For comparison the Black Watch piper's ordinary uniform, with dark green doublet)
BTW here's your photo of the Argylls pipers reduced to fit the size of the page here a bit better
Wow look how open they're playing "C"! The PM was one of THOSE guys like "I want to see those fingers come all the way off!"
And no "open C" in that band!
Oh, and speaking of the Argylls this shows a piper wearing the ordinary field equipment rather than the elaborate wide black leather piper's belts
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