I have on my list a Model of 1899 having SN 35xx which shipped in 6/1900. That one is in .38 Special. As noted, earlier first models in .38 Special (up to around SN 7500) had no barrel caliber stampings, while those chambered in .32-20 were always barrel stamped as ".32 Winchester." These are historic S&W revolvers, the first of the K-frame hand ejectors and the parent of over 7 Million K-frame revolvers made over the past 119 years. The usual references state that 20,975 in .38 Special and 5,311 in .32-20 were made until 1902, so they are not plentiful, especially considering that probably a large percentage of those made did not survive into the present time. You are fortunate that yours has its original extractor rod knob. They are often missing and are impossible to replace, although some replica knobs exist. While it is likely shootable with modern standard velocity ammunition, I would recommend that you do your shooting with a more modern .38 Special revolver. A broken part will be very difficult to repair as there are no replacements. I won't speculate on value, but I do believe the amounts previously given are conservative. Any serious S&W revolver collector will want at least one 1899 in his collection, even if it is cosmetically challenged as yours is.