Any help you guys can give me on this would be greatly appreciated.

A while back I was cleaning my 6" MkII (standard barrel, fixed front and rear sights) and when removing the upper assembly from the frame, I dropped it right on the front sight.  Well needless to say this was not good, but thankfully the only damage I could see was that half of the retaining pin for the front sight was broken off and the sight blade became very loose.  

So I took it to my local gunshop and they installed a new pin for the front sight and it is now as solid as when I bought it.  Problem now is that the gun shoots about 2" low at 10 yards. It looks like the front sight sits in the same position as before the "accident" so I can't understand why it would be this low when it shot fine before.  

Any suggestions on how I can fix this problem?  I am considering just buying an adjustable rear sight an using the elevation adjustment to fix the problem, but I'm not sure if the adjustable rears sights will work with the front sights that come on the fixed-sight models.  Also, I'm having trouble finding any affordable sights on the internet.  I only paid about $150 for the gun so I'm not about to spend a bunch of money on new sights.  

Thanks in advance for the help.

Did he replace the front site blade?

Just have your smithy file down the front site if you want a elevation adjustment.

He did not replace the front sight.  I never thought of filing down the front sight.  I was thinking of it backwards - I was thinking the front sight was too low.  That makes it a little easier now that you say that.

I have been known to bring files to the range.
Of course make sure it's empty and pointed downrange when filing. Final finish at home.
That takes the guesswork from "how much to file off?" Good luck.