-
It looks like a 10mm axle with loose bearing seats.
If so:
buy this:
Shimano XT Front M10 Hollow Hub Axles - TWO FOR ONE! bottom of page
install with 10mm less spacers on each side (hard part)
done! :) -
The HB-M525 axle has M10×1 threads to accept rear wheel hardware, and steps down to 9mm at the dropouts. Much easier to spend £10 than to mess about with saws and files. You'll may need some chainring bolt spacers to get the OLN to 100mm and with the wheel in the middle.
Whoops, thought you used that mod a few years back.
In that case, @larsenroad, SPNK/Walker Brothers might also be able to supply bearing seats (although better suited to later HED hub aesthetics):
https://www.lfgss.com/comments/12421970/