These are coming up on the bay regularly at the moment, the individual cards can go for between 5 and 20 quid, however there are a couple at a bin price of £15 that have gone around probably 5 or 6 times. The sets of these gold cards however ( there were 3 sets of 3 released ) can go for up to £200 as they seem to be rarer than the single ones
Hope this helps