Just in case you are looking for such a solution; I have created a powershell script that makes a backup from a replicated (Hyper-V 2012) VM. To do this correctly it pauses the replication while the copy is in progress. Additionally it adds a timestamp to the name of the backup, so that backups do not get overwritten.
It's a cheap & simple solution, but so far seems to do the trick, as long as you keep an eye on your storage ;-)
Script can be found here: http://www.servercare.nl/Lists/Posts/Post.aspx?ID=117
Regards, Paul www.servercare.nl