Your supplier, nlsolarheating/solartubs, imports them from China and charges you 4x the cost. I imported a system from lucky, the quality is very good. Have a look at the article I referenced from "International Journal of Photoenergy"
Of course, if you primarily need electricity then you could put up extra panels and run a heat pump. I don't know about Canada, but in USA I can buy a 4 ton air source heat pump for $2k. In your climate though you would probably need a ground source rather than air heat exchanger, which will cost more.
I'm sure the supplier in Canada orders them from China but in high volume probably full container and so it gets a much better price not to mention lower shipping cost than I will pay for just a few tubes.
And yes they will have some profit margins but likely they tested multiple China supplier and got the best one (I can only test one).
Still even ignoring the cost of the thermal solar collectors thermal solar costs more and last much less as there are thermally insulated pipes and high temperature water pumps most will requite maintenance and a few replacements over 25 to 35 years.
As I also need electricity it allows me to have a much smaller LiFePO4 battery as I can use the large heating PV array to charge the battery fully even in worst overcast days that battery saving alone is worth more than thermal solar collectors.
Air to air heat pump will not work here as is way to cold in winter and geothermal is just way to expensive. Also a heat pump will not be able to recover the investment even $2000 over the usable life at just 2 cent/kWh that is the cost of energy from solar PV. From grid with price of 15 to 20 cent/kWh the heat pump may be able to recover the investment but not from 2 cent/kWh as there will not be enough saving to recover that $2000 initial investment.
Plus you need a much larger battery and larger inverter to run that heat pump and you need pex and pump as you can not heat the air (you can but then the battery needs to be huge).
There is just no way to make savings in my installation by replacing anything with a heatpump even ignoring the lower temperature here.
Total cost is 12k most of that is for solar PV panels. You can reduce the size of the PV array to buy the heatpump but then you need to also increase the battery size and inverter thus making it way more expensive. You need to think about the entire system.
My house needs about 1000kWh for heating in January (coldest month here) so you can design a system capable to do that and cost less than the one I designed. If you try to do that you will understand that adding a heat pump is significantly more expensive.