I received an email from Sportsman's Guide saying they had some ammo in stock and more on the way. I browsed through the "in stock" list and this is mostly what I saw:
7.62x54R, Extended Blank Ammo
8x56R Mannlicher, FMJ-BT, 208 Grain
7.5x54 French MAS, FMJ-BT, 139 Grain
2 3/4", 12 Gauge, Rubber Buckshot
Winchester DryLok Super Steel Magnum, 10 Gauge, 3-1/2", 1-5/8 oz.
Federal 28 Gauge, 2 3/4", 3/4 oz.
7.62x39, Blank
Home Defender Nova-DR 12 Gauge Blank Distraction Rounds
PPU M200 Standard Blank Ammo, 5.56x45mm NATO
If you want to scare your target they certainly had a good selection of blank ammo. Otherwise, since I don't own a 10 or 28 guage nor any guns that shoot the rimmed European ammo, I didn't see anything that I needed to order.