Need More Cow Bell

So I have come in to some vintage bicycle bells recently. I bought 5 of them where the advertisement on ebay said that they were not working and all had problems. I opened them up did a little tightening and 4 out of the 5 work like a charm. I haven't even cleaned or lubricated them yet.


From what I can tell these two are German. This first one says "Made in Germany" and from my research, post the second world war Germany was stamping goods with "Made in West Germany" or "Made in East Germany" or "Made in DDR" or even "Made in Germany". The interesting thing is that the two handles have "D"s engraved on them. I will most likely never know when some of the bells were made.

 The bell below also has the D marking but no mention of where it is made. I thought all products for the past 100+ years had to have a designation? That "D" and the geometric pattern on the top makes me think these are from the same maker. The bell below has a "59" on it and a much less complex ringing mechanism which makes me think it was made in the 1950s and is post war while the one above I am betting is made prewar or right after the war before they changed their labelling and probably just assembled and shipped out whatever parts they had.

Possibly I will never know because the bicycle bell historians are hard to come by. I also tried polishing them up but they are tougher to polish then they look! i barely made a dent in the rust. I am going to have to try some spot treatment or invest in some oxalic acid which guys on the forums are talking about.