It will fit your 2017 Silverado Crew Cab. There are 4 color options to choose from:
Jet Black: 10300
Ash/Gray: 10301
Cocoa Dune/Tan: 10302
Saddle/Brown: 10303
The under seat storage is only available for the extended cab. For the crew cab the behind the seat storage is what they make for your truck, https://www.sharptruck.com/du-ha-behind-the-seat-storage
The only stipulation for the underseat storage is if the truck has a factory installed subwoofer. If it does this will not fit. Otherwise they have made them to fit.