Port, Polish and Port Match

I've got RHS Pro Action 64cc, 200cc heads on a forged 383 with a comp nitrous cam -CL08-301-8. Looking for a little more HP. Ideas on how much HP I'll gain from a port and polish and port match? Running a Perform RPM manifold. I know I've got room to move on the cam. Looking hard at the Comp XR294-HR. Any experience and comments on that cam would be appreciated. 700R4 with 3,00-3,400 stall.

Cam currenty installed- Part number CL08-301-8 NX276 HR 224/236 at .050, .502/.52, 113 separation

Cam I'm looking at- XR294HR, Part number 08-443-9, 242/248 at .050, .54/.562, 110 separation

Thanks all!