TA still offers their Pro 5 Vis crank arms in 160mm, but finding an importer might be an issue.
https://specialites-ta.com/pro-5-vis...nivelles,170mm

Otherwise, BMX crank arms come in lengths down to 110mm; you can expect to do a bit of fiddling if you intend to run a double or triple ring setup.

Finally, Mark Stonich at BikeSmithDesign has a crank-shortening service:
https://bikesmithdesign.com/Short_Cranks/index.html