you cna purchase just the lock and cylinder. here is a illustration fo the parts for the console on your truck:
item 4) Lock and key
www.lakechevrolet.com
parts > your model info > collion parts > console > center > lock and key. i cant ge tit to bring up a price but it comes up as 0.00 youd have to email them. they are very good source for oem chevy parts though. i got my whole console unit for like 400 bucks with shipping verse the 696 the dealer here quoted me to get it. ... good luck
-krazymatt