NMs drop runes, those can be traded in for the equip pieces. Give the runes to Rowena in Ul'dah.

I know that the YG links are dead, will replace them when a decent replacement is available. Till then, please use your own sources.
Item FNM Rune
Buccaneer's Boots Pulling Fangs Menphina
Buccaneer's Sash Pulling Fangs Thaliak
Buccaneer's Shirt Mammoth and Master Althyk
Buccaneer's Tricorne Shuteye Azeyma
Harlequin's Acton Mammoth and Master Nald'thal
Harlequin's Belt Mammoth and Master Oschon
Harlequin's Cap Pulling Fangs Nophica
Harlequin's Tights Shuteye Nymeia
Templar's Chain Coif Pulling Fangs Byregot
Templar's Haubergeon Mammoth and Master Rhalgr
Templar's Sollerets Shuteye Llymlaen
Templar's Tassets Shuteye Halone
Table written by Niya Kouya @ Sargatanas, member of Moogleschubsers LS.
Item Links and drop data by yellow gremlin (no longer existant).
Final Fantasy XIV is © Square Enix Co., Ltd.

Other projects: NM Table | Beastmen stronghold chests