Finally found the spin-in strainer that fits!
After purchasing other spin-in strainers that didn't fit the threads in my sink, I purchased the Danco 86800. It works perfectly and appears to be well constructed. And FYI, My sink is at least 40 years old, so this may be the spin-in strainer for you if you have an older sink and are experiencing the fitment problems that I encountered.
Verified purchase: YesCondition: New