Oooo oooo! I know a bit about this! Last year, a friend broke his Z-spar casting on his 192 during an unfortunate mast raising debacle. (The 192 is the 222's "little sister.")
You can get parts from
www.rigrite.com. The new mast foot and base plate won't look anything like what you've got now - don't be too scared.
The new mast plug will not be as vertically thick as the old one, and will not have sheaves to exit halyards at the mast base. There will be a thick white starboard space block. Block goes on deck, base plate on block, and new mast plug into bottom of mast.
Since the halyards no longer exit the mast base through the plug sheaves, you will have to cut new exit holes in the side of the mast. You will also have to buy new stud blocks, which bolt into holes on the side flanges of the new base plate. You'll also have to get new trim plates for the exit holes. All of this stuff is available on Rig Rite's site, but it's not very well spelled out. You'll also have to get new 316 1/4-20 bolts that are longer to accommodate the spacer block. I recommend McMaster-Carr for that
www.mcmaster.com
I am deciding about buying a 222. But the Z par mast foot has a broken "ear". Can you switch the mast foot for the DMACO stainlesssteal foot?