Going rate was around £250 on ebay last year, seen some at shows for about the same. Pair of Isri high back captains chairs fetched £500 recently (must be silly season)
Depends on condition etc I recently paid £150 for mine, but one has a broken arm that's going to be 'entertaining' to repair...
'The Bobdogs'
Some mornings, it's just not worth chewing through the leather straps.