What are you looking for in a roller cam? Low end torque? Mid range?
Swapping the parts over from the LT1 bottom end to the Vortec should work out okay. Not sure what style pistons the LT1 engines use, but since the L98 heads have such a small chamber you'll have to keep a close eye on the compression ratio. I have a roller cam for sale that I used in my Vortec engine. It has less than 2000 miles on it and in excellent shape, it would save you a few bucks compared to buying a new one. Shoot me a PM if your interested. Not sure if you know also but Vortec blocks require a special timing chain so I'll include it in a link: