I would try sending them an email via the Stoves website to their technical department. They offer to sell spares direct, so once you know what is required I would have thought any reputable repair engineer would be able to fix it for you.
Only clever chappie I know in that department is Alan Cameron from Alacam in Olrig Street Thurso, but there must be someone similar in Wick.
I am assuming it is out of warranty of course.
Best of luck
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