Rick,I believe you were mistaken in your opening post when you wrote: "The Canadian Govt. of course did it's level best to keep these young men out (just as it did with European Jewish refugees during WW2)."
In fact, the Canadian Governmnets of the Vietnam War era, under Prime Ministers Pearson and Trudeau, were quite welcoming to draft resistors and, as well, to deserters. Landed Immigrant status was easy to get and many, like my friend Jesse Winchester, became citizens and stayed permanently.
The Yellow Door, the Montreal folk club at which I did my basic training (pun intended) 30 or so years ago, also served as the office and drop-in centre of the local committee to aid draft evaders and deserters, so I got to know many. Leaving home and family behind on a matter of conscience, without knowing if they'd ever be able to return, was not something that was done lightly by most. For many, coming to Canada was an act of courage.
Mike Regenstreif