What makes you think it was originally bronze? Early Techs were normally brass, plated in nickel or gold. I do not see anything that looks like bronze at http://mr-razor.com/Rasierer/Tech/Tech.htm.
Here is a pic with a Gold handle beside for comparison
Maybe more copper colored than bronze?
On closer examination I see a tiny fleck of gold at the top of the handle. Now thinking its just a gold that is missing all of its plating and this is the copper under-plating. Would look cool re-plated in copper and lacquered.