On Monday, May 19, 2014 8:56:21 PM UTC-4, Michael Terrell wrote:

I've been looking for the connector HP used to connect to the 355E/F
attenuators. No one shows any stock. The MOQ from the OEM is 1K, at $28
each. It was a seven pin Winchester circular plug, HP: Connector (7-pin,
male) 1251-1037

These guys http://www.veracitytechnologyservice...obsolete-parts say they have your part.