Cheapest priced copy (Commander Masters): $0.35 at Card Kingdom, near mint, their price list as of .
Explorer's Scope 
Artifact — Equipment · Common · Zendikar · #202
Whenever equipped creature attacks, look at the top card of your library. If it's a land card, you may put it onto the battlefield tapped.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)
Legal inCommanderModernLegacyVintagePauper
Not legal inBrawlStandardPioneer
10 printings · $0.35 to $4.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Forgotten Realms Commander | 205 | Common | $0.39 | — |
| Commander Masters | 380 | Common | $0.35 | $0.49 |
| Commander Legends | 461 | Common | $0.35 | — |
| Conspiracy | 198 | Uncommon | $0.35 | $0.99 |
| Duel Decks: Zendikar vs. Eldrazi | 28 | Common | $0.39 | — |
| Final Fantasy Commander | 344 | Common | $0.35 | $0.79 |
| Jumpstart 2022 | 766 | Common | $0.39 | — |
| Fallout | 231 | Common | $0.35 | $1.99 |
| Fallout | 759 | Common | — | $4.99 |
| Zendikar | 202 | Common | $0.39 | $2.99 |