Q: How do I create a VPN between my Macs

If this is for streaming media it could be done VPN across that distance is not the way I'd want to rely on it. I'd seriously consider a portable USB or flash drive. One power outage or crash or crappy network connection to your media server could shut down your operation. Would you rather have 2600KM of wire to troubleshoot or a 1 meter USB cable?

The simplest way to deal with this would be to use something like LogMeIn Hamachi. I know that at one time, it was free for up to 5 clients. I don't know if that's still the case.

Teamviewer is free for non-commercial use, it would do the job.

Depends on what you want to do. Back to my Mac is free as well...

Teamviewer doesn't have VPN for the Mac, currently, it can VPN with a PC.

I'm not sure Logmein Hamachi is free anymore.

Back to My Mac may work when configured correctly.

However, I can recommend Pertino - free for 3 devices (per network)

I can stream Plex from my media server to my computers across the city. I think the Pertino bandwidth is about 2-4mbps for that connection.

TeamViewer will connect to any computer running any version of OS X back to Leopard, all TeamViewer connections are secure, you'll get the full bandwidth available to your connection. I connect from Chicago to my London office using it, at 150Mb/s. Where do you get this info from?

Set up and use Back to My Mac - Apple Support