While a skilled gunsmith can replace staked on front sights, sadly there are few that have the experience to do it right. Most people will advise if you really want to change sights on a gun with a staked in front, to simply have it dove tailed to a standard dimension like Novak.
I would probably just send the slide to Novak and they will dovetail the front and install front and rear of your choice. I have not used them personally but hear they do good work at a fair price with reasonable turnaround time