Any managed hosting company who operate their own racks would probably agree to it, though since most good managed providers put an SLA on their servers you'd have to keep spares, etc, onsite if you wanted the SLA too.
What exactly is it you need managing?
█ Dan Kitchen | Technical Director | Razorblue
█ ddi: (+44) (0)1748 900 680 | e: [email protected]
█ UK Intensive Managed Hosting, Clusters and Colocation.
█ HP Servers, Cisco/Juniper Powered BGP Network (AS15692).
The trouble is that I need another person to do the management (keep it secure and apache, mysql running well).
Why not pick the colo you want, build the server with the OS and the software you want then just hire a respected server management company that supports BSD admin like Rack911 or Serverwizards? I'd pick a company that can do ACTUAL admin (not just Panel admin).
Many data centers / colo companies have management packages but you will usually pay a lot for it vs. a regular monthly management company.