Due to occassional stall at idle and on deacceleration, my mechanic pulled the OVP today and by comparison to other OVP information on the forum I found the following -

The unit was shrouded in a removable black plastic sleeve,
The unit is alloy and has a red top but has TWO 10amp fuses.
The unit has TWO 30a poles.
The unit was manufactured in "Hungary" part number 89 7236 000

It tested fine electonically, however, there is corrossion on the 87L pole (which incidentally powers the ICV), and rattled real bad.

The replacement aftermarket unit is identical and has the same part number, however, the box shows part 201 540 37 45, cost AUD$149 approx US$105.

The supplier advised that this Hungarian unit had replaced both the original Siemens 000 540 52 45, and it's replacement 000 540 67 45, and claims he sells heaps for W124, 126, 201 and 202.

Posted for interest.