Demon Hood Gasket

They are certainly available used, but a quick check at steelerubber.com shows this one:

70-1640-43.....$ 32.70/ea.

Weatherstrip, hood to cowl. Replaces #2217348 & #2785695.

1963-65: Valiant, Dart, Belvedere & Dodge (exc. 880)
1965-69: Valiant, Dart, Barracuda
1970-74: Valiant, Dart, Duster, Swinger (may match others as well)

Grant