I have recently acquired a Beolab 1700 (cheaply!) which has one of its black 'buttons' missing.  These are the metal bits that pass through the front slot and locate into the switches - size approximately 25 x 30 x 3 mm.  It should be plain black ie no red lines.  Does anyone have one of decent appearance in their spares box that they would be willing to sell?  I am pretty sure these bits were used on other applications too.  Many thanks.  Peter