The Dual field was shipped with yellow headphones. Quite often folks have the headphone changed out for better ones. Probably where you've seen blue phones.
Gold Bug Pro to help alleviate my life long gold fever. No luck
XTera 705 w Big ass coil tuned just for rings in the dry.
Whites Surf PI Dual Field for the wet, and going swimming.
Rods for Sewer
Mine came new last year with blue phones, have not seen them anywhere else, and my whites buddies swear I got a refurbished unit. Note: When I bought them, Kelyco stated they would come in blue on the website.