I have 2 Lee Loadall-2s - 12ga, 16ga and conversion kit for 20ga for either of them. They can be bought for about $70+/- from various locations. They are easy to operate, work well for me but not as robust (not abuse-proof) as MEC, Hornady or Dillon or such.
Ballistic Products has Cheddite primed hulls in stock as well as a decent selection of wads . . . and presses.
Powders are still difficult to find.
Get a Lyman Shotshell reloading manual for load recipes for nearly all gauges/hulls/powder combinations.
Good on you to help out your grandson and get him introduced to reloading. My grandson is too far away for me to do the same.