No affiliation, don't know anything about it. But they're rare as hen's teeth...
http://www.sr20forum.com/mechanical-oem-part-outs/260036-1991-nx2000-5spd-hard-top-part-out.html
http://www.sr20forum.com/mechanical-oem-part-outs/260036-1991-nx2000-5spd-hard-top-part-out.html