Can't remember if it was here or at
http://www.flu.org a guy was talking about selling his steel rims with glamour rings, just this week.
My '80 came stock with glamour rings. Unfortunately for your question, the '78 came to me with aftermarket rims, and no before pictures.
Do you really think they will add all that much if you have chrome hub caps? One more thing to polish, one more thing to get curb rash.
Plenty-o-folk have switched to mag or alum wheels, keeping their steelies just in case. Ask around, bet some would be willing to part with the glamour for a few sheckles.