I've finished writing something for this, although I'll see if I can get Pim_gd to take a quick look at it before adding it to my thread.
Whilst looking for the mods to recommend in the comments for that dialogue, I also came across:
Wedding Veil and Wedding Dress (short) in
Kir's thread, which has adjustable breasts (perfect if your new waifu is a flat-chested girl or a trap).
Her Wedding Ring, by
Faceless.
Wedding Tux from
Dante's loader thread - won't work without the loader, so don't complain if you're trying to run it on vanilla SDT.
Edit: It's done, and in my thread. Link in my signature.