Hi. Actually, it's not pressboard, it's layers of different veneers. Commonly done by mannufacturers to save cost, they criss-crossed several plys of lower grade veneers to cut down on warpage, and put mahoganny veneer on outside. How long has the creek been dry? What is your weather like, there? I fear that electronically, your chassis may be a wrexck. Being in weather as long as it has fine windings on coils may be ruined. Flyback may be toast.I waould also look for continued termite life in cabinet. They thrive in conditions you pulled it out of. They may be deeply in other areas of cabinet.
Look for tell-tale holes, tunnels. Termite droppings. Glad picture tube came back.
Sounds like a great tube....
In console like you have, this set is un-common, but, you may very well find one of the other table model cabinets.
Good luck on your set.
Bill Cahill
"If it lights, and leaves you with a warm glow, it's tubes."