Unless the sizing/deprime die is carbide, I would just buy new Lee .44 mag dies, along with a separate final crimp die, also from Lee. Not very expensive. Midway usually has them at very good prices. CB
If you shoot cast bullets and have trouble with crimping,you may want to try a Redding/Saeco Profile Crimp die.It does the best job with crimping into some of the deep wide crimp grooves in cast bullets that I have seen.