Look at how this went, for a pair of valves
http://offer.ebay.co.uk/ws/eBayISAPI.dll?ViewBids&item=121612228956&rt=nc&_trksid=p2047675.l2565
http://offer.ebay.co.uk/ws/eBayISAPI.dll?ViewBids&item=121612228956&rt=nc&_trksid=p2047675.l2565