To be fair, the spy's revolver is actually supposed to be a .38 special diamondback, but spymondback doesn't sound as cool as spython, I guess.
This skin looks pretty great. The wood looks pretty nice. Upon opening the .vtf in photoshop, I oticed that you didn't add any shading or lighting effects to the wood though.
At first, I didn't like the lighting effect on the cleaned up barrel in game, but I eventually warmed up to it. It's kind of like a matte-satin like bluing, which is pretty cool.
The only improvement I could really see would be to add some kind of normal map to the grip to make the checkering stand out more, and maybe add some shading to it in the .vtf. Another thing that would be neat, albeit probably out of your control, would be to make the wood more like the wood on the ambassador. If you look at the wood in the .vtf, it looks like it was drawn with a sharpie or something, and it really works with the game's style. It's by no means a must, simply because the game's style shifts a lot between weapons (ambassador, shotgun, sandman all have different wood styles. Ubersaw, axtinguisher, and decals are all different styles of blood, etc), but it would be kind of a neat thing to keep in mind.
Overall, the wood grip is a nice change, and the tweaks you did to the rest of the skin are all pretty sharp, and well-done.
Bananite