Delta did produce a "Norm Abrams" special edition Unisaw.
But I think the OP can safely find a random/generic Unisaw from the 'Norm-saw' vintage and get the switch part number off that. IMO *very* unlikely Delta used a unique switch.
Most likely a common switch housing will fit....
EDIT: Ah, here we go:
"Dated: 7-22-96 MODEL 36-900 LIMITED EDITION NEW YANKEE WORKSHOP UNISAW The 36-900 Limited Edition, New Yankee Workshop Unisaw is equipped with a 52" Unifence, with table board and lower shelf, and features chrome handwheels, carbide-tipped saw blade and a personalized, engraved nameplate."
-Mark