Gambieras may be tier 0 but the material issues are much larger than they are with jacket. Compare the two:
Jacket:
Staghorn Coral: Legion or VW from Tsui Gorab or Toucan for TOAU
Penelope Cloth: Legion or VW from Fjalar or Brekekeke
Befouled Silver: Lord Ruthven or Hahava drop
Malboro Fiber: Cassie / Eve / Many BCNMs (Biggest Risk is people vendoring)
Rest all are commonly available
Gambieras:
2 x Ormolu Ingot Legion or VW from Vanskavarik or Penguin in Uleg
Aht Uhghan Brass Ingot: Cannot obtain ingot, can only obtain ores from certain assaults or mining in Halvung
Pelt of Dawon: Tier 3 VNM or random drop from Tier 3 Jeuno
Black Solleretes: Requires a Kunwu sheet, which is 3 Kunwu Ore or 1 Kunwu Iron. Only obtainable from Bahamut / Ouryu / Campaign in Fort Karugo Narugo
The materials for Gambieras are much more annyoing to obtain. Then you also toss in the relative cost difference for leveling gold versus bone and 100+ for both sounds right.