For a turret prop for games 6 or 7 UDIMs sounds like way too many. This depends on the resolution of each UDIM of course, but as @Joopson mentions throwing more resolution/UDIMs at it is probably not a reasonable way to solve it. In production, you will have a resolution limit that you will need to stay at/under, so making…
This is one of those situations where there's a real distinction between 'can' and 'should' You absolutely can use 7 texture sets on the turret and there's no reason to not use 7 texture sets on the turret if your use case justifies it i.e its big and important and you're taking full advantage of the resources you're using…