Window regulator- 1930 Mulliner Box.

[Austinsixandahalf]

So now I can see the regulator, I can understand why it will wind down (gravity assisted!) but only partly up. Both the quadrant and the cog it meshes with are very worn. Comparing a spare ?Austin-Healey Sprite regulator quadrant (which I feel certain was common to many BMC vehicles), it is pretty much identical - and indeed could be used to replace the original item. However the original cog is of a different diameter so would not mesh. 
Would appreciate any advice here please. Don’t really want to go the way of a rubber wedge to hold things up!

[Austinsixandahalf]

Bit of an update here. As you will see from the pic below, when the extraneous pivots and metal are taken off the Spridget sourced regulator, it is VERY similar to the original Seven item.
Now fitted and working as a temporary measure with an incorrect handle.