As you have been Artificer, I have tried to do a web search for more info on the cantle. I have searched for highland soldiers in the Boer War and the only reference I can find to sporrans were white ones that had the affect of being a target for the boers to shoot at. The only pictures I could find of around that era were paintings of soldiers of the Black Wtach who were all wearing the horse hair sporran with what looks to be a leather cantle. I have been able to find a photo of what I believe to be a similar cantle with bag that was auctioned by a military auction house (see below)





I am also posting a diagram that was posted in another thread, sorry I don't remember by whom, but they deserve the credit (has a similar shaped bag to that in the photos)



I dont think the sporrans with the hangers have provision for a strap to be attatched to the cantle so you would use the hanger to attach to your kilt belt.