There are a few ways to obtain these Service Medals, and we will list all of the different methods here:
1) Do World Quests in Warfront zones when your faction controls it. Right now this only includes Darkshore and Arathi Highland, but there will presumable be more Warfronts and included zones in future patches. Your faction will need to control the zone for these World Quests to show up, and the controlling faction gets 5 World Quests each day they control the zone. Each WQ gives you one Honorbound/7th Legion Service Medal, so you can get a total of 5 Honorbound/7th Legion Service Medals per day per controlled zone.
2) Complete Faction Assaults. These show up every 19 hours after one begin (12 hours after one end), and last for 7 hours at a time. During this time you can go to your map to see special Faction Assault World Quests. Each faction has 5 of these WQs up at a time, but you only need to complete 4 of these to progress on the main Faction Assault Quest. This short quest first requires you to complete 4 WQs, then a small mission that typically takes a few minutes, and after this you are awarded with 5 Honorbound/7th Legion Service Medals.
3) Do Warfronts. Each new Warfront cycle allows you to complete a quest for winning that Warfront, and these award you with 15 Honorbound/7th Legion Service Medals. Since you can only do this for each new Warfront cycle, this typically gives you 5 extra Honorbound/7th Legion Service Medals per week now that we only have two active Warfronts.
4) Open 7th Legion/Honorbound Paragon Caches. You get these Paragon Caches for every 10k Reputation you obtain after already being Exalted with 7th Legion/Honorbound. Each cache gives you 20 Honorbound/7th Legion Service Medals. This method of obtaining the Service Medals is the only one that is not timegated behind daily resets or Warfront cycles, and there should pretty much always be a way for you to grind these reputations; either from World Quests on the other faction's continent, by doing Warfronts, doing Warfront WQs, running Island Expeditions etc.
What to buy with Honorbound/7th Legion Service MedalsThere are some interesting items for sale that requires Service Medals to buy. The vendors are called Provisioner Stoutforge for Alliance, in Boralus (TomTom coordinates: 66.82, 25.68, behind the boat) and Provisioner Mukra for Horde, at the Dazar'alor Docks (TomTom coordinates: 51.23, 95.05, near the portal trainer and quartermaster).
Some of the items you can buy include:
- Cloaks in basic faction colors (red or blue) for transmog.
- Heirloom items, including 3 trinkets (75 Service Medals each) and a tanking cloak (50 Service Medals).
- Four different mounts; 2 for Alliance and 2 for Horde. You get a Krolusk mount in your faction colors for 200 Service Medals, and a Moonsaber (Alliance) or a Dreadwing bat (Horde) for 750 Service Medals.
- Some other items like a teleport ting (300 Service Medals), toys (125 Service Medals), and pets (100 Service Medals).