Postal service in Malachi

Hi there,
I am a member of the Postal History Society of Canada and recently I acquired the old envelope shown in the attached photo that was postmarked postmark in Malachi.  I was wondering if anybody could share any information on how mail would’ve traditionally been handled in Malachi.  I’m assuming it came and went on the train, but was the train station used as the post office?  I’d also be interested in any information on Chas. H. Robinson and Malamute Lodge that could be shared.
Any digital photos, especially of any building that was used as a post office, would be greatly appreciated.  The likely extent to which I would use the photos would be in write-ups for the periodic journal of the Postal History Society of Canada, in which I would gladly credit the person who provided the photo.
Many thanks for any consideration you can give to my out-of-the-blue request, and I hope all is well.
Jason McLellan
Member 1610 – Postal History Society of Canada
jaymclellan101 -at- gmail.com