You might try the Canadian Sea Spray Club. I know that even 2 years ago there was a fairly active fleet in Southern Alberta, had facilities on Lake Newell I believe. I saw at least 5 of them for sale around Calgary in the last year.
I believe the /nationals are to be held at lake Newell in 2013.
I think they were racing the 15's, but someone there might know who or where to put you in touch with an 18.
http://www.canadianseaspray.com/
http://www.newellsailingclub.com/news-events
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Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
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