Those are the same arrows I've been shooting for the past 5+ years. Love them.
Believe the outserts I use are steel. Purchased them from Lancaster Archery.
I build my own arrows. Takes some work and special tools to make sure the outserts n arrows spin true prior to gluing.
Use a Ram Arrow Spine Tester tool to assist in building, indexing, etc arrows. Costly tool, but darn worth every penny to me.
Index each arrow to mark the stiffest side. Align this with the cock vane (straight up) and your arrows will be the same. Believe this is important due to the small diameter arrow shafts.
Use Smooth-On MT-13 epoxy to glue the outserts. Just need to make sure the shaft is slightly roughed-up with sandpaper and both are clean.
Once had an arrow that didn't shoot a fixed-blade broadhead the same. Off by 8-10" from 50 yards. Inspection revealed the index mark was off by 90 degrees. Re-fletched the arrow and all was good.
Outserts are aluminum alloy and tougher than woodpecker lips!
If you don't have this tool or have access to one, I can build your arrows. Just get them to me (free service too).
Outserts can be a pain without the right tools.