u didn't lose a gb8, i'm insisting that it's not worth half as much as ur price, due to many reasons:
1.slimes are rare, lvl60+ slimes are even more rare, so slime items aren't price competitive
2.there are many items that gives more +str, which is a slime's main attribute to add (str, dmg)
3.this item has medicore stats, and dex is a useless stat because the effect of dex on a cool down time is not very noticeable
i'm posting this in the wrong place, but it might help you later on.