I bought this organ in October 2015. I found it for sale on donedeal.ie. I am fairly sure the keys are ivory. It is marked as style 604 with serial number 108514.
The stop list is as follows from bass to treble:
1 Forte, Octave Coupler, Sub Bass, Violin Dolce, 1 Diapason, 2 Viola, Clarinet, Voix Celeste, Seraphone, Wald Flute, 2 Flute, 1 Melodia, Flute Dolce, Dolce Tremulant, Vox Humana, 2 Forte
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