Hi Paul, looks like you found 2 very good options! You would do well with either the Buescher or the Yamaha. I can't remember how the Buescher is, it's been too many years since I've played one but you would be getting maybe more old-world craftsmanship with that one. Yamaha's might play easier and feel better… try them out if that's at all possible, if not, I don't think you can go wrong with either.
As for a good mouthpiece a highly recommended one is the Selmer S80 also called the C star. I have a review on it here: