Are you definitely done having babies? Make sure you definitely aren't having anymore! If you are sure about this then I would say just go for it. My boobs are still quite big but they are so saggy now and one sags more than the other which bothers me. If I wasn't having more babies I would definitely get them done.

My boobies are flat patties now! When I can afford it (in 5 years probably), I'm going to get a Mummy Makeover in Thailand where they do them all the time. I've got to heal my separated abdominals though first and lose a little extra fat. (The Mummy Makeover involves boob job and tummy tuck.)
Your boobs aren't going to return to their former size naturally unless you build and maintain a milk supply again so I reckon if you want to, go for it! Just make sure you do lots of research on your surgeon and don't go into debt for it.
Good luck!

Boobs have definitely changed shape. More of the deflated look rather than more evenly rounded. Was a full 12B, now more a 14 A/B depending on bra, but I have heaps of trouble finding comfy bras that fit properly now. So they might be kind of the same volume, but shape has changed.