If you Google "Model Engineering Clubs, Somerset" , there are several listed, Minehead, Taunton, Westland and Yeovil, West Huntspill, East Somerset SME, etc.
Since Clubs meet at least monthly, you stand a better chance of finding tools, / materials, at sensible prices, and probably in better condition, than at a swapmeet, or what is effectively an engineering car boot sale.
Additionally, the vendor will know what it is, and what it is used for.. Many stall holders may not!
Find a club and join. You will find things that you want, and advice on how to use them best., along with some face to face camaraderie.
Howard