Social Media Sales

We, SilverMane Media, publish glossy equestrian magazines. In the process of marketing these mags we have grown various Facebook sites, Sporting Horse Magazine, 200 000 followers, International Racehorse Magazine 75 000 followers and International Show Horse 20 000 Followers. I've been looking for a Social Media Sales agent that can target International Brands.

We have had contact with half a dozen companies but the interest seems to always be the same, they want to manage these sites not sell on them. Is this a portfolio that exist?

Your thoughts appreciated.

Johan