Most dye kits can be brought from the Black Market, a NPC shop.

You can also buy them from other users!

There are a few special dyes such as a Random dye kit, Uldavian dye kit and Trance potions that cant be brought from the NPC shop.

Random and Uldavian dye kits can only be brought from KIR's prize shop or off other users and the Trance potion can be brought from the CS (cash shop) for CP (cash points) or from other users!

The price of a dye kit depends on its colour ^^

Good luck :D