Yes, there is: between 1460 and 1475 Norway (if not junior partner of a PU) or Norway's PU senior can get the "A Strategic Marriage" event, giving them the opportunity to sell those islands to Scotland in exchange for a royal marriage and 200 ducats (oddly, Scotland spends 100 ducats if it decides to accept, but Norway/Norway's senior actually get 200). If Norway is a PU junior, it can contest the senior's decision to sell the islands and declare an independence war, but the AI will never choose this option.
If Norway is in a PU, an AI senior has a 90% chance to propose the deal. If AI Norway is independent, it will propose the deal only roughly 8.25% of the times.
If AI Scotland receives the proposal, it will always accept the deal.
If you want to see the event code for yourself, it's located in "Europa Universalis IV\events\flavorNOR.txt". The first event of the chain is "flavor_nor.5"
You could do a small mod that modifies event 9075 (found in "Europa Universalis IV\events\HolyRomanEmpire.txt") by removing this line:
Doing this will make the game perform all of the usual integrations of vassals that happen with the last reform without actually changing your tag.