Backup over WAN

I have backup exec 2012 with 4 rotating external hard drives but im looking at setting up my own NAS but would like to also copy\backup this information to a remote office over a VPN. Any suggestions on how to copy that information over?

My setup is two physical servers each running two virtual machines of server 2008 r2. Right now a full backup occurs once a week with about 1Tb of information, with incrementals occurring everyday but Sundays. I have a WAN link at each location of 40/10. To limit the amount of data I was considering only copying the simplified recovery of the virtual machines and possibly doing less full backups, any advice?