Hi Priya,
You need to create the PA & PSA same as 3000 cc, after creating your new company code, as you said remaining all are same then you can copy 3000 pa & psa to your new company code, after this you need to assign your new cc to those PA in assignment.
If you copy then all the Gropings of will also copied as same to your new company PA & PSA.
And you need to run Inter Company Transfer action for those employee's & if you don't have this one then you need to go with Org.Reassignment & no need to terminate employee's.
You need to create a specific nomenclature for your new company PA & PSA as per your existing nomenclature for creating PA & PSA.