The Tempest Set DOES cost 573 Coins, right?

Hat: 68
Robe: 90
Gloves: 68
Shoes: 68
Cape: 83
Epaulet: 83
Belt: 15
Earrings: 45
Weapon: 68

Pick 8.

Not part of the set:
Ring: 45
Pendant: 45

All 9: 588
Without robe (cheapest): 498
Without cape: 505
Without epaulet: 505
Without weapon: 520
Without hat: 520
Without gloves: 520
Without shoes: 520
Without earrings: 543
Without belt: 573

It's 573 with everything through the ring. It's 663 if you want the belt, earrings, and pendant, too.

The ring and pendant aren't part of the set.