Hi Enrique
My original link was to the catalogue of those records held by the National Records of Scotland. Those records have been digitised and are online at scotlandspeople.gov.uk. There IS a record for Marion Campbell or Stewart and the specific catalogue entry for that record is
"Wills and Testaments"
National Records of Scotland, Reference Number: CC9/7/36
[https://www.scotlandspeople.gov.uk/ ScotlandsPeople] (accessed 27 August 2023)
Surname: Campbell; Forename: Mareoun; Date: 24/4/1668; Description: spouse to James Stewart, of Torrens, burgh and parish of Glasgow; Type: Testament Dative and Inventory; Court: Glasgow Commissary Court.
The date of the record is the date her testament was confirmed so she died before that date. It's a testament dative and inventory which means she left an inventory of her possessions. You can download a digital image of her inventory from the ScotlandsPeople site but you'll need to pay for it (and register for an account if you don't already have one). Be warned - Scottish handwriting of that period can look like lace if you're not used to it!