Most of the items sold by the "Emblem Vendors" are for different slots but there are a few overlaps.
Their item level scaling is as follows:
Frost: 264 - tehcnically the best gear although there are exceptions
The higher the item level the better the more powerful the gear is, although ilvl isn't everything, as say the 245 'Mark of Supremacy" hit trinket could be significantly better for you than the Herkumi war token (264) if you have 0 hit.
You'll also see that they sell items titled "Crown of the lost vanquisher" or similar - DO NOT BUY THESE...EVER they are utterly useless at this stage as they give gear of the same item level but since you can now but T10 from vendors of your armor class shop you're wasting your JP.
Since people are telling you to buy daggers i'm going to assume you're a rogue so here goes:
Head over to Langrom's Leather & Links near the alliance bank in dalaran (look at the steps, it's 2 shops to the left) - one of the leather armor vendors there will sell the T10 Shadowblade gear, which is item level 251 but the set bonuses make it effectively better than the 264 stuff you can buy at the frost vendor.
As for daggers, you can buy 2 of them from the Arena Weaponry vendor in the Dalaran sewers as they are ilvl 264 so even with the useless resilience stat on them they will be the best weapons you can buy without doing ICC 25 or ICC 10 Heroic - even then daggers have a fairly low droprate...just ask Ross or Zaev!
The catch is the main hand costs about 1500 honor and the offhand about 700, so you'll have to spend the day doing battlegrounds in order to get them - Keep in mind that the weapons will be Redded out as you require an arena team rating to buy them, however since the game's arena seasons are over you can now buy anything that required 1950 or less rating regardless.
Hope this helps
*Edit* Lol Darieth i need to type faster we just said the same thing"*