I would call them with the order number handy and explain that you have received a defective even feed foot that broke in less than ___ hours of actual use and ask them to replace it.
There's no reason for an even feed to break in such a short time - they have sold you either a defective or inferior product.
There are a couple of generic types of even feed feet which are really not good at all. I would try sew-classic.com - when she has trouble with a product, she stops carrying it and I've bought several even feed feet from her that work just like the original vintage feet.
http://shop.sew-classic.com/Low-Shank-Feet_c5.htm (This page is for low shank machines - I think the 328 is a low shank, right?)
Good luck - I hope you find one that works well for you. :)