I recently purchased an early model 39A (S/N S98XX and a star stamp as well) and have a couple of questions. It's missing the butt cap and I was wondering what it originally came with and where I can find a replacement. It has a peep sight and was wondering if this is original or added later. It does not have the rear sight, just a flat cover where the rear site should be with the word "marble" stamped on it. I'd also like to get an estimate of what it's worth.