Hi Marc,
Sounds like you made a good choice in aquiring your first Bridgestone.
Can you see any rust on the flywheels, unfortunately, from experience, they are prone to rusted cranks, especially if someone has used a hosepipe to clean the engine with the side covers off !! The condition of your barrels is a good sign. Hopefully there is something else (less expensive) locking the engine.
You should find the front and rear mudguards and the chainguard were undersealed, it was hand brushed on at the factory. A bit of overkill on the front guard..........it's stainless steel.
Do as much of the restoration work as you are able, yourself. The economics of farming out an engine rebuild is not good. You would be unlikely to recover your costs in the short term. It is a relatively easy engine to work on and was designed for home maintenance.
Brian.