I have an HP 8553B RF section for the 141T spectrum analyzer with bad first mixer diodes I think. The old HP part number is 08553-6002 CR3, CR4, CR5, CR6. I found a place that says the replacement is HP 10514-8454. This is a matched quad set of diodes. Does anyone know what a generic diode part would be for this? Thanks Gary K4FMX