a Tight 9 1/2" or 10" T/A converter will still stall higher (~3000-3200) than either of the heavier (assumed) 11" verts you have. The advantage (especially with the solid cam) is the 383 motor will rev quicker and pull harder through the gears and the solid will help the smaller converter drive more like stock (i.e., more torque/response than a hydraulic) under normal driving.

A solid cam (when adjusted for lash) will idle and drive like a 10 degree @.050 smaller Hydraulic, but the faster valve action and .200"-up duration numbers will build torque sooner and rev higher. I immediately thought of the old Ultradyne NF56 lobe which is ~235@.050 and 150@.200 and .512" lift designed for an .875 (Ford) lifter profile, but in your case I would PM Fast68Plymouth and get him to send you a Comp Custom grind.

A cam such as that would definitely make a 383 "snap" a bit quicker and be more responsive and make ~15-20 more lb/ft across a broader powerband than a hydraulic, so for that reason primarily...I believe solids really help when you have a short stroke motor (that naturally WANTS to rev and needs all the extra torque it can get off the line) like a 340 or 383.