I've had a look at completed items on Ebay and there is a small market for these, although your certainly not going to make a fortune. Theres a complete set of ten of these which sold for £35.

Personally I would list yours individually (as they are not a complete set and are more likely to be purchased by someone wanting a volume to complete their set) with an optimistic starting price of between £4.99 and £9.99 depending on condition and as there aren't many buyers I'd list them as Buy It Now items.

But I'd be perfectly happy to accept that I will lose my 40p listing fees and that none will sell. I'd certainly list under antiquarian and collectable to get the US visibility.

Ebay is as good a place as any to sell them, but it would be worth having a look on Amazon to see if they are listed there then you could list for free and wait for a sale. You might have to wait a long while but if your happy to leave them on a shelf until someone buys them you may get a higher price on Amazon.