Here is an Ebay auction for an NOS C3OZ 6306 A Hipo crankshaft sprocket by the same Ebay member "baktive" with a Buy-It-Now of $175.00:
Up for sale is this new, in its original box, New Old Stock NOS Ford 289 HIPO crankshaft sprocket. This is correct for 1963-1967 Ford Mustang Shelby GT350 Cobra and other high performance Ford vehicles. The Ford part number is C3OZ-6306-A. This has been stored for many years in the shop and the box is a bit worn as shown in the pictures. There was a very light bit of surface rust on the sprocket that came off fairly easily with some steel wool. Again, this is a new NOS, never used, original Ford part. Please check to make sure this will be correct for your application. Shipping on this item is a flat $9.95 anywhere in the 48 continental United States. We only ship to U.S. addresses in the 48 continental United States on this item and combine shipping on multiple items. Returns are always accepted if you are not satisfied. Payment is expected within 7 days.
NEW NOS Ford 1963-1967 Ford Mustang Shelby GT350++ 289 HIPO Crankshaft Sprocket | eBay
-Fred-