The timing set must say it is for a factory roller cam, the gear configuration is different from retro-rollers and flat tappet cam blocks. The factory roller timing set has the gears reconfigured to fit the bolt-in thrust plate. Which also changes the chain, so you need the timing set of matched parts.
The OEM part for the roller cam comes in two versions one for pre 1996 (not L31 Vortec) roller cammed engines and another for the 1996 and up L31 Vortec with the plastic timing cover. All of these are usually a single row roller, there are double row roller sets, expect to have clearance problems with the timing cover from these, adding a gasket or two will usually solve this. It is best not to use a double row chain with the L31 Vortec as the timing cover often needs to be spaced forward for clearance as with the pre 96engine, but the 96 and up Vortec uses a crank position sensor in the cover which will acquire a dimensional miss-match that often affects the computer if you use the OEM fuel injection.
For examples I include these, not nearly all inclusive of what's availabe. If it doesn't say compatible with the factory roller block and cam; assume it isn't!
Summit Racing® True Roller Timing Sets SUM-G6601 - SummitRacing.com
Chevrolet Performance Timing Chain Sets 12371043 - SummitRacing.com