Gents,
It seems that my previous link to the Karkee Web site is not working well.
The 1944 Mk V Sten parts list can be found near the bottom of this page:
http://www.karkeeweb.com/patterns/19...net_frogs.html
There are also images from a British 1951 Mk V Sten parts list. Those images include the nomenclature for the MkII and MK III Slings, which show the VAOS numbers and drawing numbers (the drawing numbers match those listed above by Rob).
My current thoughts are that the slings in question (short and non-adjustable) are the first pattern of Sten sling (VAOS B3 BE 8574). The fact that the surviving examples are a few inches shorter than the 36” described in the British 1942 Parts ID list could have been due to a Canadian production error. There might have been a mistake where the webbing was cut to the “finished length”, and then when it was folded and riveted, it was too short. It seems that this style of sling in unissued condition, was (at least in the past) relatively plentiful on this side of the pond. Maybe it was recognized that they were too short and were purposefully not issued (ideally this would have been caught prior to receiving an acceptance stamp).
I looked through some of the CMHQ files on Sten guns, but they don’t include much correspondence regarding Canadian production (other than quantities and when to expect shipments). There were a number of documents regarding how motorcyclists should carry Stens. The attached document states “The provision of a lengthened sling for the Sten was approved in September 1942 and is now standard”.