Bari Mouthpiece Dilemma

Okay, I've got a late model King Zephyr, and exactly two mouthpieces. I'm pretty new to saxophones in general, so this is all a learning experience for me.

My first mouthpiece is a throwaway Rico Graftonite. It is ultraloud (at least, for my practice space), and sounds bright compared to #2: a Rascher piece. With a #3 legere reed (my practice reed), it is pretty close to perfect from top to bottom of the sax in terms of tone.

#2, the rascher, is dark and soft, as we would expect. This has serious advantages with my wife, who hates the baritone with a passion. The rascher is my "marital harmony" mouthpiece. While I love how it sounds, it is too large for the more modern horn (I suspect), and to get it in tune(-ish) requires pushing it way in on the neck. The sound takes more work to sound even from the high to low octaves, with the low notes sounding far better.

I like the sound of the rascher, but I need to overcome one problem: middle and high C#, C, and B are wildly sharp. It is way more than I can counteract without major embouchure changes. I can bend the palm key notes back into shape without too much effort though.

I suspect that this is just a "feature" of using a mouthpiece made for saxophones from a different era. Is there a modern mouthpiece that would give me the dark, soft abilities of the rascher without the intonation problems? Does anyone else have these problems when mating a large chamber Mouthpiece to a post-WW2 saxophone?

Any advice is appreciated. Thanks!