Hi admitch,
Since I notice a bit of a quiet spell on the board let me give you my 1,5 cents here.
I’ve been doing some repairing myself and most PW’s have been Elgin.
What I do is go to http://elginwatches.org/scans/tech_doc/1915_MC/m_index.html
Once you know the class you just page down to the Spring section and look it up.
The least expensive mainspring winder I’ve come across are my fingers 
I start from the barrel hook end of the spring carefully pushing it in the barrel.
Don’t force anything and no sharp bending just help it in.
I did order a used K&D set from Uncle Larry’s but haven’t really used it yet.
Well hope that helped.
Greetings,
Cornelio
