It is most likely a Chorus, after '87. I bought a post from a LBS in '87 that was supposed to be C-Record, but was exactly like this. The C-Record had a single exposed bolt like the later super record posts did. I still have my Chorus, and still feel a little screwed almost 20 years after the fact...but it is with a complete Chorus grouppo so I don't resent it quite as much.