I'm not sure how important to you it is to have an authentic Carello unit? A similar 'tag on' light was used on the European Fords for many years, it's an Altissimo unit. There's a couple on Ebay UK right now, maybe one will do until you come across an OEM Pantera.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2203...me=ADME:B:SS:US:1123
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3601...me=ADME:B:SS:US:1123
If you decide to go that route I have family in the UK so we can always have it mailed to them for forwarding if the seller doesn't mail direct overseas.
Good luck,
Julian
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