2001 montero_back driver wheel part...need advice

I yall! happy 2011. i'm looking for exterior part for a 2001 mitsubishi montero ltd in white for the driver's side curved part above the back wheel. i got hit in the grocery parking lot in the atl so bad while i was buying food that it can't even be fixed. what should i do as i don't have full coverage, where would u recommend looking for a part, and can u advise on a reasonable cost I should be expecting? Thank u in advance for ur help!!! xoxo -- Kate