What is the best Shockwave figure

For a while I have been wanting to get a cartoon accurate Shockwave that turns into a gun but I don't know where to get a real version of the MP 29 because there seem to be a lot of KO's. Do any of you know a trusted site where I can get MP 29 that is not to overpriced? Or are there any other Shockwaves that I could consider getting that are better?