Is this an early 70's Gibson Tar Back Bass Pickup

[scotrock]

Is this an early 70's Tar Back Gibson Bass Pickup|?

Hi I need help in identifying this old bass pickup, it has a lot of characteristics that makes me think it is a Gibson Tar Back from the early 70's a la Bill Lawrence period.

I know that there is loads of information on the web regarding the six string versions but I cannot find anything regarding bass pickups, I don't even know if they did Tar Back Bass pickups.

The construction is very similar to the early Gibson EB bass pickups, it has two magnets either side of a central rail that has been re-drilled and adapted from a six string pickup rail.

I have attached some photos of the pickup alongside a tape measure, the pole centers are 50 mm E to G and the cover looks like its been chromed.

Please help me identify it, I have never ever seen one like it although a UK bass builder called Goodfellow used resin filled bass pickups in the 80's and 90's I don't think it is his, his were moulded in resin moulds with wood grained finish.