Hi @MorganBrickley
Thanks for reaching out about this. The OSVR Leap Motion plugin is still under development -- it'll be available when the OSVR HDK is available to ship, which will be relatively soon but we don't have an exact date yet.
Additionally, we don't have an example of migrating from Leap Unity assets to OSVR core assets just yet. In the meantime, here are instructions for converting an Oculus camera rig into an OSVR camera rig.
For Hand Controller functionality:
First drag the VRDisplayTracked prefab into your scene, right underneath the Oculus Camera rig.
Select the Oculus camera rig, right click it's Transform, and click 'Copy Component'
Select the OSVR camera rig, right click its Transform, and click 'Paste Component as Values'
Drag the HandController GameObject from the Oculus object onto the VRDisplayTracked object.
You hand controller now should be a direct child to the VRDisplayTracked GameObject.
For Leap Passthrough functionality:
Select the Quad object on the LeftEye game object of the oculus camera rig.
Right click the transform of the Quad and elect 'Copy Component'
Drag the Quad GameObject onto the LeftEye GameObject of the OSVR Camera rig.
Right click the transform of the Quad and select 'Paste Component as Values'
Repeat for the other Quad
These steps should leave you with an OSVR camera rig that correctly works with the Controller.
Stay tuned for updates on this front -- thanks for your interest and patience.