Looking for Erfurt 1913 6480.

I have a blued magazine with aluminum base 6445. "u" marked with a stamp.

looking for spare mags to 1 matching magazine pistols

2801e+ Droop eagle 63 nickel body 1935
4219 h Droop eagle 63 nickel body 1936
2590+ eagle 37 marked pinned base 1940

have
2151e Droop eagle 63 nickel body
4350 h+ Droop eagle 63 nickel body
3506+ eagle 37 marked pinned base 1940

I wish there was a list of borchardt mags
 

I am pretty sure that when a Borchardt with mismatched mag pops out in an auction, somebody keeps an eye/ catalogues it's continuous provenance.

But it feels like Borchardt collectors might be playing it closer to the chest.[ But I might be wrong]

And if Luger collectors exchange and reunite their mags with the correct guns- my hat goes out to them!
Seems like win win situation