That looks like the 76mm turret that we know and love! This is the late version, which is appropriate for the M4A3 (76mm).
The end of the barrel is still a bit over-elaborate. It should just have a simple wider section at the end (it was a removable collar intended to protect the thread). Or it could have a muzzle brake, as they were being fitted by the time this variant of the turret was being produced.
I hope you can find the budget to replace the existing turret in this kit.
