The specific point is that in the Calendars of Probate, 'sealed' means that the English courts accepted that the procedure elsewhere, probably in Scotland in this case, was valid, and they did not need to institute a full process of proving the will all over again under English Law.
You can order a copy of the will from the National
Archives Records of Scotland, even though this is later than the last date for which wills can be viewed online at Scotland's People. See
www.nas.gov.ukNote that in Scots Law, there is no such term as 'probate'. The equivalent procedure is called 'confirmation' and the annual Calendars of Confirmation can be consulted in selected libraries and archives. These give the same sort of information as the English Calendars of Probate.