I'm out of that world for a few years now, so can't offer any names, but you are looking for someone at Canadian Army Director of Land Requirements (DLR), or possibly the Royal Canadian Air Force Director of Air Requirements (DAR). They are the ones who devise the equipment requirements that will be procured through either DND if it's a small enough buy, or PSPC if it is a major procurement or fleet buy.
If you can be in Ottawa this April, this event is worth registering for, as those guys (as well as other Government procurement folk) will be there in droves: https://www.defenceandsecurity.ca/CAF/caf/Army-Outlook. Try to find someone from DLR 6; they set the requirements for the Army's commercial fleet recapitalization program, which is an annual buy of $40 million - $70 million of commercial pattern vehicles and equipment for use on Canadian Forces Bases. The Navy and Air Force spend smaller amounts of money in a similar way. Apart from scoring on a major crown project that would likely require you to partner with a major OEM, those commercial recapitalization programs are your best bet to sell to DND.
The other major annual event for industry and defence requirement / procurement types to link up is also in Ottawa, this coming May: https://www.defenceandsecurity.ca/events/details&evtID=344
There are also regional events throughout the year, such as Best Defence in London and WestDef in Calgary. This organization is a good resource for companies like yours, providing resources and and hosting a variety of events designed to connect industry and government: https://www.defenceandsecurity.ca/
The Federal Government also has separate agencies that may be able to help you do business with DND and other Canadian Federal Departments. Depending where you are, look up your local reps for Western Economic Diversification Canada, Atlantic Canada Opportunities Agency, Canada Economic Development for Quebec Regions, or even the Federal Economic Development Initiative for Northern Ontario. Worst case, try Innovation, Science and Economic Development Canada.
There is nothing preventing you from cold-calling DND folk to pitch your product, but I doubt the right guys are trolling this forum. You will have to be persnickety in either attending the events up above, or trying to get points of contact in those various Agencies who can help you navigate how to sell to the Government of Canada. Word of warning - it is a slow and ponderous, almost byzantine system, that may cost you money up front. But if you win a big bid, the payoff is (likely) worth it. A small or even medium-sized company, however, has to be extremely savvy, have an excellent product, must know how to bid, have patience, and have lucky timing, to score with government sales. There are companies out there who help guys like you to navigate that system. Maybe one of the Agencies can give you a point of contact with one of them. Good luck!