Re: sale price
A roads with a stick is fairly rare as well as being a 2007. But since the cars are essentially the same thruout five years price is more contingent on miles and condition. that said, there is no comparison the an SRT convertible as they are the rare bird for which many desire as a long term "KEEPER"
Finding a good one under $20K is rare.
ALA-XFIRFE was close on his pricing, depending on how anxious you are to sell. A 2007 with those miles is young but not virginal. It might fetch $14K-$15K with summer coming on. But more likely $12K to $13K.
Prices have been fairly stable or the last few years. I don't think time will erode them much in the next year or two if the car is in good to excellent condition. gas is cheap now and driving for fun is in again. And money is getting better all around.
List it here and on Craig's list. E-bay is loaded with junkers making a fair price look comparatively high.