The Expanse action figure kickstarter

Master replicas already have a rocinante figure

https://www.masterreplicas.com/products/xl-the-rocinante

If you are into LEGO there are rebrickable instructions available. https://rebrickable.com/mocs/MOC-49304/brickgloria/rocinante-the-expanse/#details

https://rebrickable.com/mocs/MOC-23618/shawarden/rocinante/#details