Glock 45 Fiber Optic front sight recommendations

[titsonritz]

These are the right size using the stock rear sights? Is the fiber post the similar size to the stock white dot too?

They are, but I'd recommend replacing the stock rear sight. If you already have a Dawson front I'd do like @NeoBlackdog suggests and get their rear. As mentioned you don't need a pusher for that rear. I go with plain black rear though