Hi
Maybe these will be of use to someone
[http://cgi.ebay.com.au/FC-HOLDEN-GRILL-BADGE-NEW-REPRO_W0QQitemZ4614961336QQcategoryZ32058QQrdZ1QQcmdZViewItem#ebayphotohosting
Saw these (they look to be the same ones) up at Bendigo Swap last November, while they looked OK chroming was very good, they were a very heavy thick brass casting. The holden badge insert is not the original plastic badge and it was held in position using a large messy amount of silicon.
At starting bid of $130 or buy it now $150 if you want one, better than nothing.