Vintage pattern help

[Pinkie]

Hey guys, found this old pattern still in the original mailing envelope. The company is Marion Martin Patterns, is anyone familiar with that? I'm thinking this dress pattern is 40s based on the silhouette of the dress. Is this a house dress? What do you all think? All the pieces are in the envelope untouched. Thanks guys!

 

[Vinclothes]

Marion Martin Patterns were advertised in farm magazines such as Oregon Farmer or Idaho Farmer and several more. They were very inexpensive. Most patterns were for house dresses and aprons. Is there a postmark date on the envelope? Yes, it is probably late 1940's.
Marian

 

[Pinkie]

Marion Martin Patterns were advertised in farm magazines such as Oregon Farmer or Idaho Farmer and several more. They were very inexpensive. Most patterns were for house dresses and aprons. Is there a postmark date on the envelope? Yes, it is probably late 1940's.
Marian

There isn't a date on it anywhere. Thank you for your help!