oo sound in words like hook, book, took, etc., was ever pronounced like the oo in "moon"

My wife, whose childood was spent in the Scottish borderlands, despite having had most of her accent replaced by RP at a posh London school, still tends to rhyme "book" with "Luke", although not so pronouncedly as our current Lancastrian neighbours.

When she refers to the carbon fall-out from our chimney, I have occasionally made the mistake of thinking she referred to my formal attire.