Vintage Conway Stewart #420 BCHR Eyedropper Fountain Pen - One of a Kind!

Description

Here is a Conway Stewart #420 BCHR eyedropper fountain pen. I'm not able to find any information about this model, so this must be fairly uncommon. This is BCHR and eyedropper fill. It looks early so the Warranted 14C nib may be correct.
The condition is fair+. The nib has a hairline crack from the vent and needs straightening. The chasing and color are very good, but there is moderate scratching and a few scuffs on the barrel and cap. There is a bit of rubber material missing from the back of the barrel (see last picture).