I would like to get my hands on a Cardymeter as well; my general experience over the years has been that electronics (CPAP, O2 Concentrators, Pulse Oximeters) are all generally significantly less expensive purchased offshore or stateside. For some strange reason the Canadian market seems to be prone to gouging when it comes to electronics/electrical gear.
I paid $650 for my Everflo Q Oxygen Concentrators; $625 for my S9 kits; $125 for my Contec 50E pulse oximeter. Even masks are incredibly cheaper for CPAP... $300 Canadian for a Quattro versus $60 for the very same thing stateside.