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:
Yes KORG - Look at the fine print in the photo.
KORG Power Adaptor No:KA380 #16
Input: AC 100-240V - 50/60Hz 1.1A
Output: DC 15V 5== 3A