Clarion PU9590C(PRC8290)Spares wanted
 

A (very)long shot, perhaps, but does anyone have the tone circuit hybrid-Clarion Part No. 051-0619-01-for the above early 90's Range Rover Stereo?
The same part was also used in the CRH111, and was made by, or for, Clarion
so AFAIK there is no commercially available alternative device.