Most reasonably common shotgun ammo has remained available throughout the late unpleasantness. Locally, I've been able to find .410, 28, 20, 12, and 10ga birdshot, .410, 20, and 12ga slugs, and 12ga buckshot regularly.
Smith, and Wesson, and Me. -H. Callahan
Well waddaya know, one buwwet weft! -E. Fudd
All bad precedents begin as justifiable measures. -J. Caesar