I just went to the Salehoo directory and typed "fantasy board game" in the search field, and 2 different suppliers came up on the list, S&S Vegas Distributors and Buy-U-Gifts Wholesale. It's very likely that these suppliers also carry the related supplies you seek.
When I typed "warhammer" into the same search field, the supplier Hill's Wholesale Gaming came up on the list.
Unfortunately, all 3 suppliers are based in the U.S., but there are 3 UK suppliers listed in the Board Games subcategory within Toys & Games, so you may want to look through their records and websites to see if they carry what you need:
Pukator Ltd. (pukator.co.uk)
The Crafty Puzzle Company (craftypuzzles.com)
Super Tramp Ltd. (supertrampdirect.co.uk)