You generally wont see them in normal stores unless they cater to competition/match shooters. In Ottawa, of the 5-6 gun stores that sell 22lr ammo only one carries any of it. The rest are just bulk US stuff.
Premium match ammo pretty much starts at $60/brick at the cheapest stores and can easily get past $200/brick for some of the really good stuff. $70-80/brick is pretty much middle of the road for match 22lr ammo.
The ammo most used in international competition and the Olympics is Eley Tenex I believe which is around $250/500rnds.
They are all generally standard velocity/subsonic loads and aren't meant for hunting so don't really increase the range at which you can hit anything. They make an incredibly difference in the right rifle in terms of accuracy. I've shot .22" groups (centre to centre, so the hole was .44" overall) with RWS (German) ammo in a rifle with a good match barrel at 50yds with ideal conditions. I shoot 10-round .50" groups (.72" ragged hole edge to edge) on a regular basis with various brands of match ammo (which isn't that impressive).
I've seen many people try premium match ammo in regular run-of-the-mill rifles with mediocre barrels and they don't see any improvement in their groups. It's a combination of the rifle not liking the ammo, the rifle not being accurate enough to take advantage of it, and the shooter not having the skill to deliver. It's especially odd when you see people with tacticool semi 22's trying out match ammo and they don't cycle. The usual conclusion is "the ammo is crap".
Just like how racing fuel wont give any performance improvements to a Toyota Corolla, match ammo can only do so much in a non-match rifle.