Hi again,
If the watch runs when you wind it there probably is nothing seriously wrong with it. In that case you can take it to any competent watchmaker (not those guys who just know how to change a battery) and it might be OK with a cleaning and lubrication job. This is much cheaper than sending it to IWC. But you should not have the watch running for any length of time without a service, the oils dry up as the years ticks by and running it without oil will damage the movement, which is completely unnecessary.
If there is more work needed or if you want the case and dial restored then sending it to IWC is your best option. It won't be cheap, but the result will be really spectacular. I have done that with a quite worn wristwatch and the result was first class.
Best regards,
Henrik