Hi zoolander. Sorry I just noticed your message. It's probably way too late now, but the guy I sent my 400 tele macro to was Ben Vang at Camera Check Point services for photographers in Dubbo NSW. Postage costs were very reasonable, and the guy is a genius at lens and camera repairs and maintenance, with a wealth of experience.
regards
Des

Hi Des !

You bought a Sigma 400mm tele macro last year on Ebay, and I too was nearly in the auction but pulled out because I wasn't sure whether it was AF - you might remember me telling you this on the forum.

Well I too have finally won the "power ball" that is the Sigma tele macro in Pentax mount and mine should arrive in the next few weeks from Japan. YAY !

The reason why I'm messaging you was regarding the AF. You mentioned that you would send off the lens to some place in NSW and have the AF reinforced. I am considering this also. Can you tell me whats involved and give me any details of the place that does this ? And how was your experience doing this procedure ?

Kind Regards