Rohde & Schwarz CRTU-RU or CMU-200 Front module spare KB chip

[Robert763]

Hi,
My CRTU-RU (same as CMU-200) has a keyboard fault.  The soft keys under the screen don't work. It's NOT the membrane and having checked pull-ups and decoupling it looks like the P87C552 (8031 clone) keybord controller chip.  On this board the PLCC chp is in a socket and marked FMR6P.055. The controller is a FMR6T3.
I know some members broke up CRTU's. Does anyone have a spare P87C552?

Thanks in advance.

Robert G8RPI