Mike Holder in Billings, Montanna makes them you can contact him at (406) 252-8142 . He has two sizes of (Spoilers or Air Dams)

He also has a mold for a 4 inch front Air Dam, the ones we have are the 2" version. I would like to see the bigger air dam installed on a car. I might have went with the bigger one. There is a thread on this with his number buried in it farther down the page. He also sells a rear one modeled off the 69 Camaro rear spoiler.
He has several Novas a 68 and 69. He seems like a nice guy we spoke for over an hour the last time he called. He was wanted to know about fitment and quailty, basically any issues with it. I thought it fit great and had no issues with it. It was boxed up well and woked good.