I have a Winchester'94 30-30 rifle made in 1901 that has had a head space problem forever. I have searched everywhere for a way to correct it. Mainly an oversized locking block. I have purchased 4 or 5 originals and none would correct the problem.
Then I happened across Wisner's Inc. in Adna, WA. It is now as good as new. I highly recommend them if you are looking for parts for your old "Winny". Very fast, very professional and very friendly. The parts are made by them and of very high quality.
http://www.wisnersinc.com/
Ron