I’m not absolutely certain, but that looks an awful lot like this guy:
This is a Molex Pico-SPOX 87439-0601 (DigiKey part number WM13298-ND).
We carry the crimp contacts for the series here, but the crimping tools for them are not cheap for a one-time use. Alternatively, you might try a universal crimping tool, such as the Engineer PA-09 Universal Crimping Tool (known as part number “350” from Adafruit), which can be used for a multitude of contacts from various vendors, as listed here. It will not give as good a crimp as a tool designed specifically for those contacts, but it may get you by in a pinch for small jobs. In this posting, Kristof_2649 explains how to use it, though for a different sized contact, but it gives you the general idea. Unfortunately, we are out of stock on this crimper at the time of this posting. Hopefully, they will be back in stock in the near future.
We do also carry pre-crimped wire leads and full cable assemblies of the Pico-SPOX connectors, if you can use different leads. This saves you the trouble of having to crimp your own leads and pretty much guarantees a proper crimping job.