there is nothing wrong with it being slotted and screwed. It's there so you can set the timing accurately. Once done, either lock tite it or put a spot of weld on one of the bolts to the toothed wheel.wheel.

At least you'll have better customer service than "it'll be here when it's here." that's a shocking attitude to have with a customer. So you're meant to leave the car sat there until they decide when they'll sell you one!