>>1407567I shouldve said supposedly
https://www.etsy.com/listing/644755483/vintage-military-bulgarian-wwii-aluminum this in the overview sais its from the 1970s however this one
https://www.etsy.com/listing/502110922/vintage-antique-bulgarian-military?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=bulgarian+canteen&ref=sr_gallery-1-11 doesnt say its a ww2 one but it sais its from the 1940s and i cant find any other info besides this, so i think maybe 1970s was a
typo.It does however look like a soviet vdv mess kit picrel. Me being Bulgarian, I say the commies stole our design updated it abit by adding the hanging thing on the big cup. The reason why they are relatively rare i beleive is due to lack of resources in ww2 and also if they were invented by the soviets we here wouldve also mass produced them.
But thats just a theory, a canteen theory.