I am a smith, and have a skill over 200. I sell FP for 10pp per AC. This is a common price guide on Terris-Thule. If you have a hard time getting the items you like at a fair price just contact Shanter for Medium sized FP. I'll make Large or Small, but you have to bring your own Plate Molds, and take the risk of a failure on the mold.
I remind you, that I would still be taking the risk of loosing up to 60pp worth of folded MQ sheets of metal.
Shanter (the Enchanting Smith)
Terris-Thule