Stereo speaker query--Celestion DL6

Not exactly travel-oriented, but thought we'd try anyway. What might be the approximate value of a pair of English Celestion DL6 stereo speakers in good condition? They are roughly 25 years old. I'm asking on behalf of a pal.

Follow these auctions:

http://www.ebay.co.uk/sch/sis.html?_nkw=CELESTION%20DL6%20SERIES%202%20SPEAKERS%20GOOD%20CONDITION%20&_itemId=280590340468

Hi....

Celestion 'Ditton' speakers (around in the '70s) were monumental. They held their value very well.
Celestion has always been noted as one of the higher quality makes of Hi-Fi.
Best of luck with everything.