Having checked on ebay and other sources it seems that the minimum I can expect to pay for NT196 Tweeters is £5-£40 Each. Is there likely to be a problem if these, which fit down the center of the Bass/midrange drivers, with a pair of conventional dome tweeters at less cost?
Having had a further look at the Q15's since posting, I reckon, that, due to lack of space, it would be difficult, if not impossible, to fit alternative, conventionally mounted tweeters due to lack of space, so it's either 'bite the bullet' & pay KEF Prices (even for 'pre-owned' , NT196 tweeters are at least £30 each.
If they're your speakers, you need to ask if it's worth the cost of repair against buying something else. If it's a repair for somebody else you need to ask them if the cost is worth it for them.
Fair comment, Jeffrey. I'll have to inform the original owner, who had virtually decided to scrap them. Hopefully I'll be at the NVCF on 12th. May, but whether I'm likely to source a pair of NT196's there at a reasonable price is open to question.