Just make sure to contact whoever you order from and verify that it has the pins needed, often they come with keys and not the pins/wafers other than what is installed and work with the supplied keys, even if they are using old/generic pictures for their items that may include the pins/wafers in the picture as separate items.
It should also be noted that there are various OEM suppliers that GM used to make the lock cylinders, so that means that just because you have wafers/springs/retainer from one does not mean that it will fit another even though the assembled lock itself will fit and work. The internal parts can be different depending on who made it, same with the aftermarket.