Looking for Affiliates for an SEO/PPC Tool

Hi,
We at Brand Overflow (https://brandoverflow.com/) are starting the affiliate program and I have been asked to start the reach outs but I am looking for a starting point through which I can find qualified, hard working and authentic Affiliates who are willing to work with our Brand in the long run.

The Affiliate marketing won't be just limited to sign up and start selling.

NO!

I am planning of formal onboarding, product training, our objective, target industry (B2B mainly) and then personalized facilities (like custom coupons/discounts).
Is my approach right and where should I start from to find the best affiliates in our niche?

Any help would be highly appreciated.

Thanks in advanced IH <3