If you are in Laval, Quebec, then the exchange rate is going to hose you pretty bad. Most of us are in the U.S. so we're using US Dollars.
From the link you supplied, that looks like a janitorial supply place selling replacement batteries for a floor cleaning machine. That's going to be overly inflated pricing since it's directed at those that don't understand this stuff and are going to assume that they must use an OEM replacement battery.
I purchase my batteries from a few dealers down here that specialize in telecom battery systems. I'm usually seeing $200-$300 USD for 100ah batteries.
You need to find a local dealer that specializes in telecom system batteries. You may also have luck with companies that sell fire alarm systems, as they usually run 12 volt gel cells.
If you were local to me, I'd happily give you some of our gently used 12 volt batteries. I have enough sites that we usually do one or two a year. I used to give them to local ham operators, but most of those guys have disappeared.
You are correct i'm in Laval (Quebec) but you would be surprised how much i can save by buying in the USA even with the exchange rate (unless the rate is really bad). As an example if i was to buy an ICOM 7610 at RadioWorld (based in Toronto about a 5 hour drive from my place) i would pay 4712$ after adding the taxes. The same radio bought from DX Engineering would cost me 3800$ at today's exchange rate.