I concur with some other posts :
my old 156 spf has different wiper blades than the newer cars. i found the EXACT replacement from :
http://mossmotors.com/Home.aspx
and part number is : Moss part # 165-046. Part number cross references to a 1973-1976 AH Sprite or MG Midget, retails for $14.95 each. This particular part came packaged in a TEX Classic wrapper, imported from Tex in England and sold thru Moss , and presumably other MG suppliers.
Bill