The MGW Pro is the way to go. I bought mine about a decade ago and it has served me well. I have seen them on sale for as little as $80. Some folks will loan theirs for a very small fee. In the absence of one, you can use a nylon or brass rod to 'push' the rear sight out (left to right) and seat a new sight. The pusher is best for night sights (glass vials). But it is possible with a rod and 'gentle' taps.