Spindles can be a dowel rod with or with a hook, sometimes with a whorl. Just made 3 to show kiddos with. You can also 3d print spindles or even spinning wheels. I have wheels I got for under 50 that needed repairs and got them spinning. There's a local store that has rental wheels...

With a whorl that big it might be a better spindle to park and draft with. A heavier spindle makes thicker yarn or is better to ply with. But I have found comparing my spinning to stuff I bought lets me be easier on myself. As I have art yarn souvenirs in my stash, thick & thin & twisty.

Perhaps contact the person you bought it from and see if they know the other buyer. Wheels can use multiple flyers. The flyer pictured is often used for plying or art yarn.

Glad to be here! Help share the word 😁