Navik Parts

Broken Navik windvane & turret

Tha Navik USD conversion kit replaces the Navik connecting rod and the complete Navik windvane section atop the stainless steel mast.

So indeed, the USD conversion kit would be a solution for your situation.
Prices for the kit and 5 kilogram shipping are in the webshop:

http://www.windvaneselfsteering.com/catalog/3

The price for the USD conversion kit includes 21% sales tax wwhich is not charged for shipments outside the EU.