Would it be the same part no for a 04 vy? Mine doing the same. May as well get mechanic to do it while new suspension goes in. Missus reckons SCA have them?
Its hard to say a AP250 and the AP265 were used on vy commodores, I would just change the whole antenna unit as the plastic cog also wear out, the new AP971 kit is around 160 to buy but its so much worth it, smooth and and so much more quiet. You can buy cheap ones but why when a new good quality will last another 10 years and you know
Aerpro have replacement parts. Ebay are cheaper.