60k miles is rather low for a front shock replacement, unless you are doing a lot of off-roading or otherwise heavily stressing the front suspension. Did the dealer say that the shocks are leaking, or provide any other evidence that the front shocks are indeed shot?
I would recommend original GM replacement shocks, but certainly you are free to do whatever you want. If you post the last 8 digits of your VIN,
@915_Tahoe may be able to provide you with the current exact replacement shock part numbers (part numbers change over time). Then, either you can purchase original GM replacement shocks at RockAuto.com, GMPartsGiant.com, or GMPartsDirect.com for the best price, or you can use those part numbers to cross-reference and obtain exact fit aftermarket shocks.
Depending upon your mechanical skill level, these shocks are not difficult to replace. You will need a strong spring compressor to break down the strut assemblies after removal for disassembly and reassembly, and you can most likely borrow/rent a spring compressor from a local auto parts store. Or, you can bring the strut assemblies and the new shocks to a local auto repair shop, and they will disassemble, replace shocks, and reassemble the strut assemblies for a reasonable price (most likely under $100), and you can do the rest of the work yourself.