Over the years we've collected quite a few orphan power supplies, most are for some kind of music equipment.
Maybe the one you're looking for.
This one is:
Requires standard 3 prong AC cord.
DELTA ELECTRONICS AC/DC ADAPTER - 12V Tip Positive #20
MODEL: ADP.30KR B
INPUT: 100-240V ~ 1A 50-60Hz
OUTPUT: 12V ===2.5A
We believe this is for a Kawai K1.
Custom paint job - no extra charge.
Unit in otherwise perfect, slightly used condition.