>>3163448>Right now, £200 is just my price range, I'd upgrade at a later point when I can spend more.Yes, do that. When you shoot some with that Lumix camera and research more about lights, cameras and photography as a whole you'll know what to look for and upgrade to that. Again, there's no need to overkill it with the gear, you don't need much or expensive stuff for jewellery photos to get the necessary results.
Also I'm pretty sure you can make your own lighbox by yourself for almost no money, google some tutorials and youtube videos. You don't need to spend money on that.