Celestion DL8 MKII Dave - The Celestion factory was in Ipswich in the 80's - I went on a training course, and came home with them. I'd have real trouble swapping them. I think I paid £450 or thereabouts as a 'trade' price - no idea what that would equate to nowadays - they're ancient!
Celestion DL8 Bookshelf speakers review, test, price
www.hifi-review.com
Only one report of course but you seem to have hit upon a pair of diamonds there Rob! Back then in USA they were about $500 so you paid about the right price. Can I be a further nuisance and ask what amp you use with them please?
Dave.