I believe the safest way to achive this (if it's what I think you're trying to do), would be via a multiple, site-to-site VPN network.
Relevant Skills and Experience
Senior IT Implementation engineer, with over 10 years providing bespoke IT solutions.
Proposed Milestones
$200 USD - Discuss requirements and analyze current setup
$100 USD - Provide possible solutions and advise on any additional requriements
$211 USD - Implment agreed solution
$100 USD - Test and provide support for any issues
Additional Services Offered
$500 USD - Further on-going support and advice for any other required changes or implementations.
What environments are the CMS applications currently working on? i.e. Windows, Linux?
Cheers.