Amazon. Vinwox didn’t have replacement tips per se. But they are available on Amazon from a different vendor. Just match up the size.

This is the set I bought

VINWOX 3 PCS Carbide Turning Tool... https://www.amazon.com/dp/B08DKP3GDW?ref=ppx_pop_mob_ap_share

These are the replacement tips I use for the Vinwox.

YUFUTOL 3pcs Tungsten Carbide... https://www.amazon.com/dp/B07B4TZB5H?ref=ppx_pop_mob_ap_share