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X37B is in flight launched Dec 2023 but launched on falcon Heavy (or previously F9 or Atlas a non reuseable rocket) so I don't think it counts as a booster.
https://en.wikipedia.org/wiki/Boeing_X-37

Electron has reflown an engine and a tank i.e parts but not yet a full booster.
https://x.com/Cosmic_Andrew1/status/1777732417597452352
https://www.space.com/rocket-lab-recovered-electron-production-line-reflight

New Shepard suborbital only
https://en.wikipedia.org/wiki/Reusable_spacecraft
Other spacecraft only partial reuse

WhiteKnight, White Knight Two not rockets and rockets on them are only suborbital
Nothing else indicated in
https://en.wikipedia.org/wiki/Reusable_launch_vehicle

So I think this should resolve no.
@eccentricity looks inactive so @mods can you resolve please? Thanks

Not re-using it yet, but seems like only a matter of time:

https://www.theverge.com/2023/7/18/23798686/rocket-lab-electron-reusable-satellite-launch

Rocket Lab successfully retrieves its reusable rocket after splashdown

Rocket Lab, the small satellite launch company best known for its attempts to catch its reusable boosters with a helicopter, successfully retrieved its rocket from the ocean as part of its shift toward marine recovery.

https://en.wikipedia.org/wiki/Reusable_launch_vehicle#List_of_reusable_launch_vehicles