When my front shock shafts went they both snapped right where the thread starts meaning that bit of the shaft was stuck in the shock ballends with no way of removing it.
Hence might be worth getting some (unless both mine were coincidences). Part number: AS1777.
I've done a front arm so yes that is a good idea. I chewed up a spur as well so might be worth carrying one around just in case that happens to you. I got an RW Racing one as advised on here and it seems a lot better too
Hope this helps.