Or you could ask me to get you some mirror paint.
If you don't really plan on dumping a lot of money in, here is the result...
This is the stock plastic slide of a Maruzen P99. Painted 5 layers of mirror paint on it.
I will get some Krylon gloss coat to finish it tomorow.
Edit:
I scratched the paint this morning before applying the clear, so I re built the gun to see what it looks like: