We use a lot of Nikko Airking scopes in 2-7x32 or 3-9x40 or 4-12x40 on 22s. These are well made and reliable, they have Adjustable objective and they are around the $200 mark usually. You can go a lot dearer but the results I got with mine on a 22 tell me I wont get any more performance for spending more money. Leupold do a rimfire scope as well as sightron, but I still buy the Nikkos.
For something a bit cheaper without giving away much quality, the Nikko Mountmaster AO series are prtty good for a reasonable scope, though I always spend a little more and step up to the Airking if it is for me.
Most sports stores should be able to source them for you. Smiths city, Shooters supplies etc all carry them here in Chch so sports / hunting shops down your way or Smiths city would be worth a try.
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