Good morning dubbers,

Frog's had a spaz. Been having a weak crank, so jump started her yesterday.

Volts reads 12.5 whether it as running or not with no spike up when it starts (not the usual 14v at running), and voltage was slowly ticking down as time went by. However, charging light (which is definitely working) turns off. I confirmed alternator is properly grounded with continuity test.

So alternator not pumping anything back in battery, but happy to flick the charging light off.

Would anyone have any suggestions?

Thanks,
Chris.

assume internal reg alternator?

Definitely should have 13.8V at battery when running

You can get new regs but from the USA

Bugger on shipping

Pull the internal reg out, as it probably is crapped out (thats'usually 90% of any alternators problems).

Before you order ex-USA and pay the freight, the hoooogest auto-elec place in Oz just happens to live in Qld.
If they can't match it up I'd be surprised.

http://www.ashdown-ingram.com.au/product-range/rotating-electrical 
http://www.ashdown-ingram.com.au/branch-locator 

yep, should be between 13.8-14.4v when running.

if the Oz place has no luck then try the UK VW vendors as the shipping will be a heck of a lot less and the part not too much more than USA.
Dunno why USA vendors like to root us for shipping, even AusPost Shopmate is similar, yet a USA individual I've used for a few things charges things much more accordingly to weight and size.