For anyone interested, I have set up a little dedicated Ghost Recon: Heroes Unleashed server on GameRanger ( www.gameranger.com ), the free cross-platform multiplayer gaming network. For starters, it is running 9-slot CO-OP in "Firefight" mode on random maps.
No TeamSpeak or anything fancy required, just join in and have some fun!
I'm hosting from my laptop while on the road, but bandwidth should be sufficient for up to 9 players. The server is on dynamic IP, so it may go offline for a few minutes once in a while (usually every 24 hours).