I was under the impression that a FPGA for scrypt wasn't feasible. What about this report from Alpha Technology? http://cdn.shopify.com/s/files/1/0241/1743/files/Alpha_Technology_-_Scrypt_Analysis_on_FPGA_proof_of_concept.pdf?709
They are working on a GPGPU instead of FPGA.
http://alpha-t.net/blogs/news/8353976-development-update-24-07-2013