You probably want to take a look at location masteries/challenges if you want to unlock a particular item. I believe you’ve already unlocked one of the lockpick items in your inventory. Completing the mission once should grant you enough experience points to unlock it.
But in case if you don’t, there’s some other lockpick items you may unlock via Legacy Packs. Here they are:
ICA Facility – The Final Test
- Lockpick (Tool) – Complete Mission Story Challenges in ICA Facility
Miami – The Finish Line
- Lockpick MK II (Tool) – Unlocked at Level 2
Dartmoor – Death in the Family
- Lockpick MK III (Tool) – Unlocked at Mastery Level 2
The Classics Challenges
- Silent Assassin x5: Classic Lockpick (Tool)
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