Glasgow Angling Centre sell JC Capes. However, capes vary greatly in number, colour, size, of feather, and I would suggest that mail order is not the way to go if you are particular about the colour and shape of feather you want.
I too have struggled to get capes at decent prices and quality over the last two or three years. The last cape I bought was very good quality and at a reasonable price; I got it from a seller on Ebay. The advantage of this was the seller provided a picture of the actual cape before I bought it.