Yours actually might be a III, I thought mine had 1/1000s on it and that was the difference. You can pick up a Jupiter or Industar 5cm for it on ebay fairly cheap. Less than $50.00 and maybe cheaper than that. If you shoot anything different than 5cm or 50mm you will need a hot shoe finder. So your best bet will probably be 5cm. the old Russian lenses are very good lenses for the money. Some of the old LTM and Leica lenses actually have character unlike newer lenses.