the only ones they market for and L6 engine are aluminum/bronze... doesn't sound great

They have some 'melonized' gears for the V8 with the correct shaft diameter (.489-.491"), 13 tooth count even looks right... but I'm not sure if it's the correct pitch/diameter for the 235 cam?
https://www.summitracing.com/parts/ado-10456413


'59 Chevy Suburban, NAPCO