I think the cranks are these, usually sell for £40+, and a tech sheet on the Sturmey Archer site seems to suggest using a 107mm bottom bracket. Which probably explains why this un52 was in the box… will throw in for £5 with the set.
With postage now being up there around £5, I’d rather get the value of the whole set up and only incur one postal charge. Wouldn’t save much on the £20 by splitting out…