Not trying to be a smart-ass but.... Aren't the three defining marks to a Mk25 the anchor, the sticker and the coated internals? If it doesn't have an anchor, and the sticker goes eventually falls off how will anyone know it is 'special'? Nobody will know if the internals are treated, or not. Does it say 'Mk25' on it anywhere? I can't see how it'd be collectible, really. Just wondering.
On another note... I also have a P226 (9mm, Siglites, E2 grips, short trigger and SRT also). I love it. Shoots nice, though I wish the sight dots were smaller, but I suppose they are great for combat. Accurate, but not nearly as accurate as my revolver.
I've got a .22 slide for mine, too. Very versatile gun. I thought about buying the Mk25 SEALS version, but I don't SCUBA dive in the ocean much with a pistol, so I needn't pay for the salt resistant parts.