I don't
A lot of what you buy from Amazon or ebay are actually defective carbs bought as scrap metal then sold to cheapskates
All the after market parts distributors do a line of aftermarket carbs that usually work properly
So go to Oregon, Stens, Rotary or Prime Line , check their catalogues then look for a supplier near you .
You an also check the vendors "other items"
If they sell everything from car & mower parts through to food & clothing then they are a disposal agent
Some might be superceeded stock some will be obsolete stock some will be scrap.
You could also have collapsing fuel lines or debris in the fuel that is blocking the bowl needle .