"A fair hourly price according to the persons residing country" - might not be the best way to approach this. I have quite a few friends who do freelance and they earn as much as they would if they were living in the US.
You can try using platforms such as Upwork or use LinkedIn, Twitter and other networks to post the job ad. You can also test our jobs platform, it's free :) It's better to find 1 person for this who can work from time to time with you, rather than a different person every time.