Kernall

I already have the speakers from a previous car. Im budgeting about 300 for a headunit but want a standard look. Thinking of this http://www.ebay.com.au/itm/290737559274?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Hey fellas, I recently purchased a 2008 Hiace. Its got the standard MP3 CD player. Is it possible to run an amp off the standard headunit. My goal is to: - replace the front door speakers with aftermarket ones, What size are they?????????????????? - Run some 6" speaker in the rear - Run a 12 or 15" sub - Run all of this from an amp Any help / suggestions would be great. Thanks