I got done for mine by HWP last December
No fines, just had to pay for blueslip, who then demanded I have it engd, so it ended up costing me $350 (And that was a VERY discounted eng cert)
My engineer was in a happy mood, so yeah, cheap prices on eng cert.
A mate got done around 3 months ago in his R33 for a pod filter by HWP, and he copped a $70 fine.
It's up to who ever is issuing the defect notice whether they do or don't fine you, and how much it costs.