Oh, I've no idea. I'd only go to RedHat for "official" RedHat support?

Let's just say, it's pretty big.

Bonus, you don't need to hire an outside firm to administer your Red Hat servers if you just hire somebody with "can administer Red Hat" on a job req.

Here's a short list just to fill out your curiosity (the real one is likely much longer):

http://www.linuxit.com/linux-support-services/

http://www.dcvast.com/software_support_services/redhat_linux...

http://www.netdigix.com/

http://h17007.www1.hp.com/us/en/enterprise/servers/supportma...

and so on.

Red Hat as a company more or less exists these days on name brand. In fact, their EBITD margin is negative despite their stock price riding high.