| A3's gonna be around $450-500USD from a US dealer which would be the cheapest way to get one. It's still going to be over your budget of $500Cdn though.
Look around for a decent price on a Pioneer PRS-D3000SPL also which would be a great choice that can usually be had for a great price.
Also there's a Orion 2500D on this site here
http://www.canadiancaraudio.com/online/car-audio-sale/23363-orion-h2-10s-2500d.html
Which will do more than enough at 2ohm with 1200rms there (set gains correctly and you'll be just fine) and has tons of extra balls if you decide to get higher power handling drivers in the future. It's overkill for sure with basically only using half of what the amp can do but it's a fine amp that could be had for a great price (try to get it for $450 or less).
There's a couple more suggestions for you. | 
