They aren't common, but it would be difficult to justify spending £40 for something that is no better than fair on the obverse. I've only had three in the last 12 years including one in quite reasonable grade last year, but it had been cleaned and was never going to win a beauty contest. It took quite a while to shift this, despite its rarity and the fact it was priced well under book to take the faults into account.
Being a single year type for the reign will help demand, but you rarely see them in a desirable condition which is the key to getting a good price and widening the circle of people looking for one. There is some demand there, but suspect it has to either be dirt cheap, or in top grade.