If you notice the "sling" pictured on the IMA "link" above......that is a "Post-War" Yugo sling....I can't see the clip on other end to tell you if it is for the MG34 or MG42...but definately "Post-War" due to the "Hook-Style" on the other end.
The slings that MARSTAR's web-page is now showing appear to all have the "Post-War" end-hooks and not the WWII German style hooks as my photo below shows.
(NOTE: The three at the top of each photo are the "Weapon-Sling" end-hooks that attach to the underside of the barrel-jacket.).
If I remember correctly....the "Ammo-Can" slings had a "Hook" of a slightly different design than these....and it was on both ends.
Regards, RichardS in MI.Blanksguy2001@chartermi.net