The service centers that can perform the upgrade are listed below:
I would recommend that you contact Nivie in Brooklyn, (which is right next to Jamaica.. ..Queens that is). I believe that they would be able to accommodate you, but you will should settle the shipping and payment issue with them beforehand. Contact nivie@mindspring.com
Nivie Electronics @ Brooklyn Army Terminal 140 58th St., Bldg B, Unit 7B Brooklyn NY 11220 718-765-0123
Midwest Audio 774 W. Algonquin Rd Arlington Heights IL 60005 847-640-1890
Digitron Electronics 7801 E. Telegraph Rd. Suite D Montebello CA 90640 323-887-0777
Videologic 127 Pleasant Ave Upper Saddle River NJ 07458 201-327-9333