If you really want Chevy Engine Orange, as for an early '60s small-block, Testor Orange is a decent match.
If you want Chevy Engine RED, as on all rat motors and some hi-perf small blocks (such as LT-1) that's a different color--a brilliant red-orange. The old Model Master stuff was perfect but no longer available. But if you're airbrushing, you can mix it up fairly easily out of Testor #3 red and their orange.