You may want to try the new Milltown Marina which is on the north arm right by the airport on the Vancouver side. I know they are pushing for annual moorage/dry storage but if they aren't fully booked as of yet you may be able to call them and see about it?
http://www.milltownmarina.com/index.html
I would highly doubt you'd find anything right in the heart of Vancouver.
Is launching your boat daily out of the question?