Hi Bill,
My guess is that your shoulder strap was lengthened to add some strap length for a taller owner of the holster...or a fellow with a longer torso...
I have seen and had own one strap for a M1929 holster that was cut down on one end for a shorter/petite shooter. One end of the strap was cut down (lost the pinch-type connector) and was just looped and rivoted through the d-ring on the holster.
Hope this helps...
The holster that goes with your brown M1929 is the one Bender shows on page 475...
p.s. You might want to chase down a M1900 Swiss-DWM luger. I think those are the prettiest of the bunch...but since you are getting a brown M1929 Bern, you will, of course, need to also get a red and black M1929 Bern...and so another Swiss infection begins...
Regards,
Pete...