Thanks guys, I tested the tweeter and it was open circuit but there was still output from the crossover - I hooked up and old tweeter I had lying around and it worked fine. Unfortunately though these speakers belonged to my brother who passed away unexpectedly three weeks ago and we found them while cleaning up his workshop - he repaired HiFi and TV's etc for 45 years and collected a lot of stuff! My Nephew had listed them on Gumtree and sold them on Friday for $180 the pair! I would say the guy who bought them got a bargain. At least they have gone to a good home as he was excited to get them fixed up and use them, apparently he has a pair of floor standing IMF's already. I have also got a pair of Sonab OD-11's which my brother used for test speakers and am now looking for replacement tweeters for them. I will be keeping them though!
Cheers for your replies guys, really appreciate it.