I have to agree with ma here on the decoy Go Buckwing and you really don't need anymore then 1 or 2. Calls are important and you should have different types. A box call is good , but I would lean on a Mini Boat paddle for volume and sharpness to have sound travel. A pot call of some sort , I like the multi surfaces as they can give you a few ranges of tone in the one call, couple or few strikers which will as so add a difference in the tone of the pot call.
Mouth calls are good and if your starting go with a Double reed to begin with. They are a clear call and you could also add a cut type call that will offer you a raspy sound if you like raspy.

Locators are another tool of the trade , Coyote Howler for them birds. The howler will work when others will not. Save your money with the owl call , you can learn that with your natural vocals.

If your putting all the time and expence into this hunt , don't leave home with a gun that "You think will do the Job" Spend the money on a good turkey choke and I'm talking the $60.00 + range , not the cheep stuff. You shoot a choke like that and you will step over the cheeper chokes by far.Look for something in a .660 constrictionand get your gun shooting before you go. Don't worry so much about How many shot you put into the Head and neck as much as you should what you get in a 10-12 in cirlce at 30 yards. Try a number of different brands of shells , and I would start with the Winchester HV copper#5-#6

Get a good seat, something you can carry easy and quiet and sit for some time on. A vest is a great way to go as you can carry most of this stuff in it. Clippers, Water bottle, Binoculars, area things that you could add. Remember to have camo top to bottom , cover all shiney surfaces, Realtree camo patterns tend to work in most terrian.

Hope that helps ...BT