<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by Empress:
Actually I was wrong on the fare, the C fare (CHAWAII) is $2119 CAD before taxes, 7 days advance, 3 days min stay, 30 days max.
If cost is a concern of yours, maybe it's better off buying V ($1104) and paying part of a SE's fare to go along with him. It's cheaper and it benefits both... 
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Empress, are you volunteering?
NZFlyer, I think Empress's suggestions are well recommended. Considering paying about $1000 CAD or only $1500 NZD, you can get your dad a RT trip in J between YYZ and HNL is a really good deal.
There is another option that the above posters haven't pointed out yet: Your dad can also fly UA into HNL. Granted, the service and most importantly, the seat won't be as good but chances are UA will have a seat available for your dad but your dates must be flexible though.
Finally, getting an award seat in J on AC to HNL is the most difficult award to book in Aeroplan. Unless you are an AC*SE, your chances of getting a seat within 2 months of your departure date is close to zero.