Well I finally got an old one back to original.  For years I have been looking for the parts for a Stevens mod. 16 crack shot thumb safety model, and several weeks ago I finally found the parts I needed in Canada.  It seems that these parts are as rare as hens teeth.  It took a while to get them shipped down here, but they are here and I got them put on the gun.  The thumb safety was a bad design and some think it made the gun more unsafe than safe, so many owners took the parts off.  Occasionally you find a crack shot with a little slot about 3/16 long milled in the upper tang.  that's where a little button would have been.  You had to hold that button back while you pulled the trigger.  It was interesting little feature, but worthless.  I feel pretty pleased to have found the parts and and restored an old time kids gun.

Maybe I have a hen's tooth? I have most of one, missing the extractor and the spring for the safety. The end of the slider has been broken or removed so it does not contact the notch in the hammer.  It does have the thumb button and proper hammer. 

I would entertain reasonable offers or trades. PM for photos and details.

I saw an extremely nice Crackshot...I mean very, very nice...perhaps all original and pristine...with the thumb safety at an Iowa Gun Show in Oct or Nov 2013.  The research I did on the net indicates that this gun must have been made between 1904-1906 I believe.