If this is to keep as a family heirloom I would do the following:
1. Full movement service.
2. Full clean of the case (without any polishing).
3. Leave the watch without the bezel. The missing bezel is part of the watches history and possibly how it was worn. I’d continue that trend.
There is a large element of personal preference here and if you prefer to install a suitable bezel, you could well go with @Spacefruit’s suggestion as this will be fairly cheap and is fully reversible.
4. Full restoration of the bracelet (if it is to be used) or store the bracelet away and put it on a leather strap.
The above will minimise service costs and also minimise further movement away from the watches original condition.