Share contacts between users in Outlook

In the past, our team of three sales people used to use Public folder contacts to share a list of customer contacts.  We've sinced moved to a different company architecture and the IT department doesn't allow the use of public folders.  Our three sales guys are trying to figure out a way to share a list of contacts in Outlook.  Are there any simple ways of doing this in Outlook?  We do use exchange server (not sure what version) but they won't allow public folder use.