Couple points
1. Wilson seating dies are very good seater but generally not for starting to relaod. However they are certainly not cheap at $50 for non micrometer and $100 for micrometer.
2. Also they would require a larger magnum size arbor press along with a standard 7/8 press for the 300 WM.
3. Claiming to be able to use a seater die as a sizer is in the same category of the people that claim you can use a chamber reamer to make a sizer die. Flat out does not work and run like hell from misinformation like that for reference. Sorry but fact.
Pick up a good solid steel reloading press. You can buy used or new. I have two rockchuckers and one is 40 years old and I can load from 17 hornets to 408 cheytac cases. Do not pick a progressive starting out. Too difficult to learn on and too easy to make a serious mistake as the are not for inexperienced reloaders.
Quality beam scale RCBS 10-10 is ideal. Later you can go digital of some type.
Bushing dies are your best bet if it is a case you are trying for max accuracy. Go with redding bushing dies if you are doing that. RCBS, Hornady and Forester Bonanza also have good dies.
You will need a quality caliper, case trimmer, powder trickler, powder thrower etc plus vibrating case cleaner and assorted case tools for primer pockets etc.
Hornady headspace comparator will be needed for measuring and setting headspace.
I always keep a case holder with each set of dies as they can vary as much as .010 between them.
Google "Shooters Corner" and look at "The List" of equipment then call Bob White as he has tons of used reloading equipment and can save you a bunch if money. Tell him what you are doing and let him help you with dies and everything.