Seeking Commerical Telephone Support for FreeBSD?

Dave H3 asks: " Does anyone know of any U.S. based firms that provide up to 24/7 telephone support for FreeBSD? I've been tasked with submitting a business proposal to list at least three potential, established, vendors. Other than Windriver I've not had much luck. I've checked several FreeBSD sites, including FreeBSD.org, to no avail."