350 Should not be too heavy. My twin 115's topped at 45mph. Weight was over 840.
300 Suzi raised my waterline an inch or more. 52 or so mph.

350 should hit 55-58 with a clean bottom.

Before you order the 350.......might you consider the 7 Marine 557 hp outboard ?

I know......7 Marine also produces the 627 hp version, but I'd say perhaps a bit much for a 23' Seacraft.......Or am I just too conservative.......

:)

Best of success with your rig !