In Canada (well, all English-Canadians I know): the first “a” is like for the word “can” (“fan”, “clan”, or the first a in “Santa”), and the other two are like the second “a” in “Santa”.
“Canada” pronounced in the Acadian French is just like it is pronounced by most francophones in Québec, as this lady demonstrates:
Any “a” that is the last sound in any word is pronounced “uh”.
Like “chat” (the “t” makes no sound.)
However, in the feminine form of the word, the “a” in “chatte” sounds like the first two “a” occurrences in “Canada”.