I had a quick scan of their website to try and find the answer before posting my question. I couldn't see any reference to their sourcing of wool and it seems odd not to include this info somewhere - surely it would only ever be taken in a positive light? If you've got something to differentiate yourself from the less ethical merino stuff on the market then why wouldn't you ? They're not alone in missing a trick though.
No, I think it is actually quite black and white. The RSPCA Australia view is that is isn't necessary as a general procedure i.e. the way it is used as a widespread practice today. By taking a better approach to animal husbandry there are much better, more humane, means of controlling flystrike.