The cells should be direct fits in a Compur/Copal #3. Good luck finding a shutter.

Alan's right, though, if you can more or less recover your outlay on lens and board -- sell them as a unit -- you can probably get a 300 in shutter for less than you've paid plus the cost of a shutter. Either way, though, the shutter will need an overhaul. That's the way used shutters are.