https://www.rockauto.com/en/catalog/plymouth,1967,barracuda,4.5l+273cid+v8,1347106,body,convertible+top+boot,1000154. For $153
TMI Convertible Boots 22-7105-2287. For $103
1965-1966 All Makes All Models Parts | MA3463614 | 1965-66 Plymouth Valiant / Signet Gold Convertible Top Boot | Classic...