Fiskars Easy Pour Watering Can Replacement Sprinkler Cap.

Thanks to TheMADEngineer for his design, which looks like it solves a similar problem. I was not happy with my original design however so used the sprinkler pattern from his model, scaled to fit. The square hole to one side is because the end of the spout on this model can rotate around and directly pour from that versus providing a shower.

Printed at .2 layer height, I had to lower retraction settings on my corexy to get the initial layer to go down well enough. Snaps firmly onto the spout. Is a little heavy on the shower, you may want to add some horizontal hole expansion, make a test print of the first layer to make sure it doesn't seal the holes completely shut with that though.