Hi. This could almost be a standard response, as the question comes up so often.
The owners' manual might be found via Organ Service Corporation or W D Greenhill, a quick google will find the details. As for the value, realistically, it's somewhere between very little and zero.There is almost no demand for these little older organs and it's sometimes easier just to give them away. I hope that, having asked about the owners' manual, you're going to keep it and play it!