i tried harnesses from autozone and walmart...

 

i got a harness from walmart and it worked and my wires im pretty sure looked just like urs. u might just have to take it to an electronics store to have the head unit installed. i dont know of any other easy way.

 

If it were me I would just cut the harness off and put the wires togther. Assuming you have the instructions for the deck you can find out which wire is what. And for the car use a meter to check for power. And do what samseed said and take a AAA or AA batter and touch it wires to find the speakers. Not too hard to do. Both cars i've had already has the harnesses cut off.