At TOAU era 75 cap Star Ring (the NQ version) was part of the best HMP set and all good mages carried them if they could afford them. The HQ was just bragging rights and showing that you either got lucky on a synth, or had gil to waste. Star Sapphires were extremely rare on Ramuh back in the day -- if I remember correctly, they only came from the Ashu Talif fight.
Also from Fiat Lux (wotg fight) and rarely in einherjar. But yeah, super rare pre-abyssea