Advice about LCD display + numeric keyboard ?

I would like to use a serial LCD display and a 12 or 16 keys numeric keyboard with arduino, using serial interface to save IO capability for the rest of the project.
Could someone recommend me a shield ? I have seen different products but I’m a bit confused.

Not really but do you have to have 12 to 16 buttons? Tell us something about your project, what you do with that many buttons. Say if you need number pads to input options, you can do it with just say 2 to 3 buttons:

Or as few as one buttons (with an auto button):

I would like to be able to enter numbers easily, so 16 keys seem a natural choice, if there are good products available.

Maybe this one then

To have 12 keys you need 7 pins.

You can buy this for 9 bucks:

florinc: You can buy this for 9 bucks:

I remember I saw it somewhere but not where I saw it. Thanks.