Just buy some m5 threaded rod and cut to size.
Edit: stainless steel, so it won’t go rusty.
Or an M5x0.8 die and cut a longer thread on the skewer you have already.I'll remove it and work out what's what.
How hard will it be to find a replacement do we think?
what he said. I'd be tempted to cobble some sort of puller together.I want to just tell you to use more persuasion but not be responsible for you breaking it
I know mine just came off, they’re a tight fit and there is often a small amount of corrosion between the bobbins and the axle, but there really should be nothing other than a very tight fit holding them on.