That photo of the 79thNY on parade raised intriguing questions:

-are those indeed pipers in front of the regiment?
All the images of that photo that I've seen are rather grainy and I can imagine that those men are carrying pipes... but they could be swords.

-if they were pipers, were they pipers from the New York Caledonian Club or were they members of the regiment?
Note their dress: they are dressed identically to members of the regiment, not in the generic Highland Dress of the period.
Most interesting is that it appears that their jackets have three rows of buttons, a common distinguishing mark for musicians' uniforms at that time.
One possiblity is that the pipers of the NYCC wore the uniform of the 79thNY on occasions such as this.