First if you go to ashran island there is two vendors that are in the same room as the bank, go find a guard then search for the bank, in the room with the bank guys. To the middle of the room and the left of the room there are 2 vendors both have 615 trinkets which are decent.
Secondly, if you have any honor left over, go into the battle of ashran and at the start there is a vendor that has a lot of people around it usually, you can get 620 gear there.
third, start the legendary quest at your garrison, do the dungeon(skysomething) on normal to get this to drop. That gives you a 640 ring.
p.s. If you are leveling get the salvage yard early so you might be able to level up your rewards and get a early good item.
p.s.s if you are having issues getting tanks or healers to run you, start queuing and go hit the ashran pvp, while you do that and get honor you can still waste time till the queue pops, which double works for you. Unless you want to hunt down rares that are 100+ to try and get some 620+ gear also.