Why not just get it repaired, there’s a chap on here who has a quick turnaround of the gauge cluster repair
https://www.volvoforums.org.uk/showthread.php?t=143579 you’re car will only be off the road 2-3 days. The v70 one may fit as a temporary bodge, bit you’ll likely set loads of codes. Don’t know where the car works the rpm value out - may not read right putting a cluster for a 5 cylinder car in a 6 cylinder one.