I found this on PIanotech on a post from 2020 in reference to the exact part in question:
"UPDATE: In case anyone else is in a similar situation, the replacement part (and for other dongbei specific parts) is from 'North American Music' in New York. The contact I was given is Gary at 1-800-782-2694. The email contact is usapianos@yahoo.com."
I have no idea if this is current information or not.
These pianos were made in the Dongbei factory, where Nordiska and other brand pianos were made. These slow close mechanisms were prone to break after a couple of years.
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Paul McCloud, RPT
Accutone Piano Service
www.AccutonePianoService.compavadasa@gmail.com------------------------------