I want an 8-bit parallel-in/serial-out shift register for a little project. What shift register should I buy?

I've used the 74HC166N, check the datasheet and see if that is what you're looking for.

Yeah, Thanks! I will try to order it soon. I like how it is also serial-in/serial-out as well as parallel-in/serial-out.

The serial-in is to facilitate connecting more than one in series for a 16 bit or larger parallel register. It's not an input like parallel data, it just gets passed along to the final stage where it can be read by your mcu. Hope it works for you.