Yes there are only two on the Silver Star, one per Viewliner. Traveling in Christmas week my wife usually makes the reservations in March as its a very busy time.
I've taken the train to Montreal when it was NYC/D&H in February. Spectacular scenery starting with the Hudson River just out of NYC. We were scheduled to do it a week ago to Montreal and then take the Ocean to Halifax. The Ocean is an overnight trip with some very interesting equipement purchased from the British for a failed overnight train to Paris. It does however carry a stainless steel round end observation dome car for first class passengers. Unfortunately my wife injured herself (she's OK now) and we had to cancel. It looks like a trip well worth taking and if you book your "cabin" as VIA calls it early they do have one with two beds both on the floor so no one has to climb up. If you're interested in a VIA trip I would recommend calling them as all of the agents we dealt with were wonderful--even haning on for almost 30 while I fought with my credit card about a charge in Canada.
