Yeah - replacing the front sight on a stock 1911 isn't too hard but it does require some specialized tooling...and it's pretty easy to get wrong. If you google replacing the front tenon sight you'll get a bunch of info, but you'll need a front sight staker at the very least from Brownells or elsewhere - and while they're not expensive, they're also very much a single purpose tool. It's not like you can buy one and use it for a bunch of things...and it's not like you're going to need to replace your front sight all that often (unless you botch it the first time around).
It's way easier to ask a gunsmith who's done it before to do it again for you. Since Colt managed to slap it together without refinishing it, it shouldn't require you to hog out the underside of the slide...there's already enough room there to set the sight (otherwise yours would have flown off by now!)
Also if you just want a set of sights, you might be better off asking on places like 1911forum or 1911addicts - there's plenty of gunsmiths there who remove the original sights before installing new sights; you might even try just emailing Novaks and asking if they happen to have any extra sets of takeoffs laying around. IIRC they send the original sights back with the slide, but it's possible they have some just laying around anyway...
Though, depending on how fancy you want to get and how much you want to keep the original kind of look to the gun - you might investigate cutting the slide for a CZ front sight...they don't use a cross-slide dovetail; they actually tap in from the front, and look like a part of the slide. It's different but it looks pretty slick.