If you have time to get to a store to buy a circular fluorescent light - it can give you a low power ringlight. They sell various sizes - but you should be able to find one that screws into a regular lightbulb socket. There's a plastic piece that supports it, but you can rotate that to the side so you can stick your lens through the center of the light. It's not real bright - but you can cut a piece of artboard or put aluminum foil on cardboard behind the light to make it a little more efficient. The photo below was shot with that setup. I just used an electric cord with a lightbulb socket to screw the fluorescent light into. I used a superclamp & gaffers tape to hold it all to a lightstand & just held my lens through the center of it all. It's not fancy - but it kinda works.
John
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