User blog comment:B214/Question and Answers 2/@comment-25222726-20140608152055/@comment-1359322-20140608152601

All Sacred Gears are common, it just depends on the ability and rarity, some Sacred Gears have several of them only, while some have many. The only ones that are one of a kind are Longinus.

Hmm, i don't see that there's any need to replicate Sacred Gears, unless if it's a Longinus cause there are bound to be Sacred Gears of the same type after all.