There is a Schwinn Museum here in the Chicago area with a pretty extensive collection; they loaned us (Chicago Botanic Garden) some bicycles for a display on toys for our annual holiday exhibit. Perhaps they could help. I don't have a contact at my fingertips; if you have trouble unearthing them, call Roger Vandiver (708) 835-8273, the Exhibits Manager at the Garden and he could point you their direction.