It's a pretty big case. While I've never used the Lee hand press, I have loaded 500 S&W and my guess is that after loading 50 rounds on the hand press, you would justify a bench mount for ease of use in sizing the big case.
You can pay now, and everything will be easy. You can save money now, and pay extra everytime you load. The plus side is you will have your bench mount and it will load anything you may decide to pick up later. Bite the bullet and get a good bench mounted press.
If it were me, I'd scour the pawn shops looking for a used Rockchucker press. Prolly pick one up for 50 or 75 bucks.