As a heads-up for the 20 gaugers, Bass Pro Shop has the Federal Heavweight 7's in the 2-3/4" & 3" shells in stock right now at a decent price. You can have your order drop shipped to a store near you and save shipping costs altogether.
http://www.basspro.com/Federal-Premium-MagShok-HEAVYWEIGHT-Turkey-Load-Shotshells-with-FLITECONTROL/product/12092909485135/#chart-container
Federal also offers a rebate on the Heavyweight shells, so that makes the prices even more attractive.
https://www.federalpremium.com/downloads/promotions/2016_Spring_Turkey_Promo.pdf
If you are in the market for a great 20 gauge commercial load, now is the time to jump on this.
FC
Gander Mountain has always had them in stock when I needed them. There is most always a free shipping deal going also.
http://www.gandermountain.com/modperl/product/details.cgi?pdesc=Federal-Mag-Shok-Heavyweight-Lead-with-Flitecontrol-20-ga-3-1-1/2-oz&i=449399