No idea what’s in it, but
FW makes a
RG upgrade pack and
etched brass
Mk.
VI beakie helmets are fairly common. Some with bling are in the vet kits.
The sternguard kit has a shoulderpad that looks like large wings spreading up from a bird skull. It’s the one in the upper left in the sprue pic on
GW’s site.
As for cool looking armor, either something fancy from
FW or the vet kits is still going to be your best bet. You can look into other ranges, but might have to scrape some iconography off.