Any love for a 373 SB

Yup!
340 w/360 crank = 367. A 22 cube gain.
367 -> 378 = 11 cubes.
Grand total over the 340 to 378 = 38 cubic inches larger over where you started.
4.04 vs 4.1
4.00 stroke, 410 - 422.
4.15 stroke, 425.69 vs 438.33.

Pick your parts and to play. What ever suites you.

4.000 ID vs 4.040 ID + $ for 340 vs 360 + special crank