with the canbus controlling you stereo, i dont think there is a way around the harness, i bypassed the system on my 04. there is a scosche knock off on ebay but i dont know anything about them. its only 42.00 and they have a 14 day return policy.
http://www.ebay.com/itm/Radio-Stereo...sories&vxp=mtr
the steering wheel interface is only 30.00ish
http://www.ebay.com/itm/BRAND-NEW-PA...item3f1c99d4ea
crutchfield is way overpriced on accessories, i would try ebay or amazon first. then
http://www.sonicelectronix.com/ or
http://www.onlinecarstereo.com/. you may get luck and stumble across something on craigslist.