Congrats on the find. Be sure to let it settle in with your system for a while and just listen to it before pushing to make upgrades too quickly. While it might have older caps and tubes, it can be very enjoyable to get acquainted with it as-is too.
Whatever caps and tubes you decide to go with also depends on the rest of your system. After listening to it for a while you’ll decide to leave it alone for a while longer or start making incremental changes. It might be okay as-is too, ya never know. Sometimes the caps in side have already been changed too, worth checking.