I made a separate post with links where balls can be bought online. Also SD can get them, just let him know.

We discussed at the coaches meeting that the rule was implemented because in previous years the quality and storage conditions of the balls being provided for league play was called into question many times for various reasons (mushy/frozen/old, etc). Hitting your own ball allows the league fee to be lower, but also puts the responsibility on the coaches to determine the quality of the balls you want to hit (ex. leather vs. synthetic, new vs. used, etc).