According to a yahoo group I belong to, only 24 WC SD45's remain. They are as follows:
WC 6497, 6529, 6605, 7495, 7498, 7501, 7502, 7504, 7506, 7507,7514, 7515, 7519, 7522, 7524, 7525, 7527, 7530, 7531, 7532, 7551,7554, 7637 & 7638.
So far the ones I have gotten that have been retired are: 6550, 6593, 6604, 7496, 7510, 7512, and 7585.
And here's the complete list of SD45's I have gotten in the year i've been shooting pix:
http://emd_sd_60.rrpicturearchives.net/locoList.aspx?mid=94