I saw these today in the Perth CBD store. There was 1 of the OMX680 and about 3 of the PMX680 left. I have checked store stock around Australia and stock levels seem to be OK. Click & collect is available for these as well I think.
DSE says you are saving $40. StaticICE has the cheapest for around $15-$20 more than this special.
Here is a link to the OMX680: http://dicksmith.com.au/product/C6752/sennheiser-clip-on-spo…
Here is a link to the PMX680: http://dicksmith.com.au/product/C6753/sennheiser-sports-pmx6…
http://www.rebelsport.com.au/eng/product/adidas-sennheiser-o…
Combined with http://www.ozbargain.com.au/node/85320
Take it to $42.49 with free shipping. If you can be bothered.