Boat Roller Kit - for existing Roof Rack

Hi all,

I would very much appreciate any advice on where I can purchase a Boat (3.8m tinny) Roller Kit that can be fitted/removed for an existing ARB Roof Rack.

I've seen a couple of different systems (Rhino etc), though I want to also be able to carry some light gear on the roof rack under the tinny when it's up there.

It doesn't need to be fancy, as it won't get used that often, though it needs to be sturdy for the corrugations

Thanks in advance and regards,

Greg