Adventure Moto Australia currently have Harley Davidson specific for 112.50 +10.00 postage, plus if its your first order with them and you sign up for their Newsletter you can get a 20.00 voucher code. That's 102.50 delivered anywhere in Oz.

Heat Demons get pretty good reviews and come with a 5 year warranty.

Plenty of install videos on youtube.

I don't know what they are like to deal with, I was searching for some and these popped up, just thought I'd share it.

Cheers.