£3k is a not a lot of money, for a lot of people. It does make me question if there are actually any bona fide collectors out there in RB land. I lived in Spain for nearly a decade, and there are literally hundreds of very serious bicycle collectors, some with collections worth millions of euros (I've seen a few of em, it doesn't half put you in your place!) There are very specific collectors also on the continent. I've seen a collection of over 100 ex pro time trial bikes, each with it's own team helmet and skinsuit. The guy will regularly pay 20k for a rare example. I'm a member of a Vespa club (I've got a 70's version) and people regularly drop 5-10K on desirable, collectable, and above all rare bikes.
Like I said, 3k is nothing to a lot of people, and if you are really serious about collecting British bicycles, it makes no sense not to snap this up.