Where can I buy 1067 MHz DDR3 for my iMac late 2009?

iMacs do not use standard DDR3 DIMMs.

The 2009 iMac uses PC3-8500 204-pin SO-DIMMs. Crucial and OWC are considered the Gold/Silver standard (and have Mac model lookup tools on their website to direct users to the right memory), but anything of above-average quality should work. Avoid budget-tier brands, which are more frequently problematic.

There is nothing special about the memory for this model - it uses standard DDR3 DIMMs.

Therefore any reseller should be able to help. Without knowing where you are it's hard to be more specific (for example, your profile name implies you're in Moscow, so a US-based retailer isn't going to be much use to you).

> iMacs do not use standard DDR3 DIMMs

I beg to differ - at least, maybe I was wrong by using the term 'standard' if that implied you could plug any-old DDR3 DIMM in, but DDR3 comes in multiple speeds/pins/variations. My comment was more that there is nothing unique about these chips and any DIMM that matches the appropriate speed and pin counts should work. This is true for all the various flavors of DDR3/4/5 :)

www.macsales.com or crucial.com iMacs are EXTREMELY sensitive to using quality RAM. Buying from "any reseller" is not wise. If you are locating in the USA either vendor is fine, if you are outside the USA then I'd go to Crucial.com.

However considering spending any money on a 13 year old computer, well I sure wouldn't.