I whipped up two potential designs just now. No scoring, as that would take a while. I think the resin plastic will shatter well enough without it.
For your consideration, two pictures. One is a plain cup, the other has a lip on the top to help capture the shot and in theory make it easier to close without fussing with over shot cards and so on.
I can run a print, 35Whelen, if you're interested.
Bulldogger