I recently bought a server that can host up to 6 players for me and my friends to play on. I haven't really used it that much however tonight i was speaking to one of my friends and inspired by syndicates hunting optic we'd like to start this in the same way.
The server is externally run which means It's 24/7 and doesn't have any lag, so you and your friend can play on it at anytime. The world is unlimited so you can go away and get supplies e.g base, or equally go out looking for enemies. We are looking for 2 sets of 2 to play this with us (however if you had 3 or 4 this could be arranged) Message me on skype to talk about this and get the IP
Andrew.Cook2011