Well its not blued so dont blue it...LOL It has Tenifer treatmentin the metal. The "bluing" is actually just a black powder coat. Send it to Glock and they will redo it for about 40.00. It wont be any less protected if the black is worn, if you just wanna leave it.
Other wise changing out the springs and such should make it perfectly fine....most police guns are carried a lot shot a little.