Cheapest priced copy (Duel Decks: Elves vs. Inventors): $0.35 at Card Kingdom, near mint, their price list as of .
Inventor's Goggles 
Artifact — Equipment · Common · Kaladesh · #218
Equipped creature gets +1/+2.
Whenever an Artificer you control enters, you may attach this Equipment to it.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
2 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Duel Decks: Elves vs. Inventors | 55 | Common | $0.35 | — |
| Kaladesh | 218 | Common | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 20 September 2016If the Artificer that entered the battlefield leaves the battlefield before Inventor's Goggles becomes attached, Inventor's Goggles stays as it was. If it's already attached to another creature, it remains attached to that creature.