Joe Gibbs & Lucas Oil both make great conventional motor oils in their Driven Series and Hot Rod lines. You can also run straight 30w Lucas if all you're doing is warm weather driving and they also offer a conventional ZDDP additive which is great for solid lifter motors.
https://www.summitracing.com/parts/jgr-02006
https://www.summitracing.com/parts/luc-10679-1
https://www.summitracing.com/parts/luc-10063-1
IMO, stay clear of Synthetics unless you want the car to start leaking everywhere. Transmission and Gear oil can also be bought through both of these manufacturers. I also run the Wix filters or the Purolator One filters.