Interesting. I haven't been able to find either here in Oz for a couple of years.
The LGS told me Federal were no longer selling 338 Fed cases as a component. No doubt they can't be bothered ordering them in. If I want correctly head-stamped cases I've had to buy expensive premium 210 Nosler Partition factory loads. I've found that simply necking-up .308 brass has its draw-backs since drawing some of the shoulder brass up into the neck forms a "doughnut". Not such a problem when loading my preferred flat-based 200g Woodleighs that don't seat that deep, but could cause concern with 210 Scirroco or SST's.
PRM , have you used the Starline brass?

Jack