Broken Nikon D40 flash, how much to fix?

It took a fall off of my bed. The flash clicks to pop up, but won't open (I've unscrewed it and found the small trigger piece has actually broken). The flash will go off if it is up or not. When I manually flip it open and it flashes, it overexposes whatever I take a picture of. Like, the flash is a lot brighter than normal. I know I can buy an external flash and all, but does anyone know what is causing this problem? - or does anyone know how much it costs to ship and fix it?

Just give Nikon a call and get an estimate on how much it's going to fix the problem.

Shipping cost?
Several different factors such as how it's going to be shipped such as
Which shipping company such as USPS, Fedex, UPS, Total Weight, Size of the box
Ground
Three Day
Second Day
Next Day
Early AM
Also have to consider on where you live and the ship to location.

You don't fix it… Nikon must.