PVP crafting - accumlated salvage mats
That looks like a Consumable token in the 2nd row from the bottom ( looks like a piece of paper) You can use that to craft 1 Unidentified Dye. The Unidentified dye will be account-bound I believe so you will have to use it and either then decide if you want to keep the dye or sell.
Otherwise I would use a combination of your Arcane Powder, any of your Equipment Tokens, and Aracane Sliver (highest rarity of the 3) and your Paid Tournament Tokens. Or you can use the Free Tournament tokens instead but I’ve found better luck with the paid ones.
You could try your luck at making Dwayna’s Longbow- Click the link for recipe. It has a random chance of giving you one of 4 longbows apparently so you have a small chance of getting them with only 2 tokens.
http://wiki.guildwars2.com/wiki/PvP_Dwayna%27s_Longbow
Or go to http://wiki.guildwars2.com/wiki/PvP_reward
And scroll down for a list of rare weapons, when you click on them it will give you a recipe on how to craft one.