Brainstorm

Common2 versions from Signature Spellbook: Jace · all sets

Cheapest version$2.48TCGplayer market price

Signature Spellbook: Jace2018

Draft Booster in 70% of packsany version · 100% per box of 36

VersionPriceDraft Booster

Regular #3 $2.48in 66% of packs100% per box

Foil #3 $5.571 in 8 packs99% per box

"Any version" adds up the chances of each version, so it is a close estimate.