Dating Seabag/Duffel

[ELINN134]

I am looking to date this seabag/duffel. Based on my research, the rectangle snap pocket did not come into use until the ‘70s. However, the US stamp does not scream 70s font. Another thing that is throwing me off if the grommets and contract stamp are nearly identical to a 1961 seabag. Any help is appreciated! 

[Kwc27122]

Looks to be post WW2.

[Salvage Sailor]

+1

 

Cold War pre-1974, outside pocket but only one (1) strap

[ELINN134]

Thank you both!