The pieces of my guide are somewhat mystifying...I don't see how it could work-harden...It doesn't flex, or twist, or bend...It travels in a straight line and [theoretically] doesn't even move (in relation to the parts around it)...
My pieces do show some crystallization, but the loose piece was reciprocating back & forth and the end & cavity have been peened by that motion so it's hard to tell what happened...
Hopefully, someone more familiar with these models can add their comments...
Pic attached...
On the mainspring: There is a guy on eBay who advertises NOS flat mainsprings -
http://www.ebay.com/itm/EARLY-GERMAN...-/160944562499
I bought one a couple months back, when I thought mine was broken (it's not), and it looks new, just some very slight rust freckles...Doesn't look home made, and doesn't look like it was made lately either...It looks original...
I was going to keep it as a spare, but maybe I'll put it in...Just in case I decide to shoot it...
He seems to have quite a few of these...They're on eBay almost every month...
I did ask Wolf if they made the flat mainsprings...they don't...
I also ordered some 1095 spring stock to attempt making one myself...For emergencies...But the Luger flat mainspring is a weird gauge; not Metric and not Yankee either...