Joe -
I would start my Shure support. It may take a few tries, but they have a couple of women who use to work in support that knew every part for those older (discontiuned) microphones.
http://www.shure.com/The Data Sheets on Shure's web iste list a 7A, but not a 7B model:
http://www.shure.com/datasheets/guides-discontinued.htmlReplacement Parts
Most replacement parts (and many accessories) for Shure products are available through our Service Department, including selected replacement styli (needles) for phonograph cartridges. For information on purchasing these items, please contact the Service Department directly.
You may phone us toll-free at 800-516-2525 or at 847-846-2699, or contact us by email at
service@shure.com.
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