Don't know about cost, but I'd assume it will cost more than the pants. Definitely worth doing. I've never done it on a suit, but I did on a shirt and it improved it greatly. Nice buttons won't be cheap either.
I am the same size as you, and I just bought a Borelli that was reasonably slim fitting (although not hipster slim.) I think a lot of the more expensive brands are cut larger, because their typical clientele are older / larger, but they usually have some slimmer fitting styles.
Visited the STF warehouse the other day looking for a birthday present for a friend. (Of course, I wound up buying a suit for myself, 'cause that's what SF does for you...) Hadn't been since he was in Venice. It really is worth a trip if you are visiting LA. Kind of like the top floor of Nieman Marcus, but at wholesale.
And iff anyone needs a proxy, I'll be happy to provide the service. My fee will be a very moderately priced trinket off their shelves...
I think it's actually the narrow leg on the pants that makes the shoes look clunky rather than the other way around. Not that it's a problem. It reminds me of the old skinhead look of my yoof.
However, while the suit fits okay, the sloped shoulders seem to make your head look very long. You might try a shirt with a larger collar to balance it better.