There are two corporate (? I don't know what to call them actually) Post Offices in Halifax and many other associate post offices (we think of them that way) in back corners of drug stores like Shopper's and Lawtons.
The corporate ones are a business solutions post office connected to the sorting plant and a philatelic centre post office downtown for the tourists on the waterfront and cruise ships.
We still talk about the associate post offices as real post offices as they are presented to us this way. The employees wear
Canada Post uniforms but are paid by the drug stores.
The Post Office I remember 30 to 40 years ago that I went to to get money orders to send to stamp companies in the States was in the back of a drug store so they were doing it back then in the 70's and 80's.
There used to be many regional or area post offices that are now closed that were
Canada Post corporate (using this for lack of a better word). The mail would be sorted there I think, before the large sorting plant was built. Modernization, machines, etc, etc.