Specifically the Crucial Deliriousness Please help this si one of my favorite yoyos.
You can either contact Crucial and ask them for a new axle, or you can head to your local hardware store and find one that fits.
Personally, I’d go with the second option as I’ve done it many times before with great results.
Think about it for a second. Crucial likely doesn’t get their axles custom made specifically for their yoyos, so there’s a high chance the axle you’re looking for can be found at a Home Depot or somewhere similar.