I have not had any contact with Dave since about 2009, and don't have a current phone number. Not sure how active the business is anymore, at the time of my visit it was a sideline to his day job. No idea if they still have or sell casting kits. For PM kits and parts I have found it is easier and cheaper to deal with PM Research in USA directly.
I would really like to find a Canadian model engineering supplier as well, so if you find one please let me know. There used to be several good suppliers in Ontario where I live but they have retired / closed and so I've been scratchbuilding everything for my models and tooling for some years now. This is far less expensive than buying supplies but takes a little longer. There are very few parts that can not be fabricated, and home casting in aluminum is very doable at low cost with lump charcoal in a firebrick forge / furnace.
There are many good suppliers of various things for model engineers in the USA of course, but with money exchange, very high shipping costs, 13% HST tax applied even on goods made in USA, and criminal brokerage charges, I can't afford to order much model engineer stuff from the USA (or UK, or Europe).
In the past at various steam shows around Ontario such as the ones at Milton, Blyth, Ilderton, Forest etc there were often some castings kits and contact info for supplies in the model areas. Haven't been to such a show in several years now so not sure if this is still the case post-pandemic as shows re-open.