Old style mainspring
 

I came across these springs today, any chance, based on the info provided, that they may work as an old style mainspring?
http://www.k-a.net/forum/springs.jpg

Nope! Sorry... the old style spring was a laminated spring... these single leaf springs would not provide adequate spring tension, or protection for the moving parts...

They would prove no harm in their original design and use, since all they do is drop a hammer when the sear is pulled out of the way.

An additional point to John's explanation: the flat Luger recoil spring has a hook bent into the upper end, with a notch filed out of the middle, to engage the stirrup connector to the rear toggle.

--Dwight

I didn't think they would work, but I thought it worth a shot for those who are having a hard time finding one. Thanks for the input:)