I'm working on a project which generates (composite) Microsoft Word documents which are comprised of one or more child documents. There are tens of thousands of permutations of the composite documents. Far too many for users to easily manage. Users will need to view/edit the child documents through the app which hides all of the nasty implementation details. A requirement of the system is that the child documents must be version controlled. That is what has been tripping me up.

I've been torn between using an off-the-shelf solution or rolling my own. At a minimum, the system needs to support get latest, get specific version, add new, rename and possibly delete. I’ve whiteboarded it enough to realize it won’t be a trivial task to create my own. As far as commercial systems I have VSS and TFS at my disposal. I've played with the TFS API some, but it isn’t as intuitive or well documented as I had hoped. I'm not averse to an open source solution (e.g. SVN), but I have less familiarity with them.

Which approach or tool would you recommend? Why? Do you have any links to API documentation you would recommend?

Environment: C#, VS2008, SQL Server 2005/2008, low volume (a few hundred operations per day)