There isn’t a good one, just the huge table from customs, but it depends on how the seller categorizes it since there are so many thousands of options.
I think it also depends on the country it is being shipped from. Again, I’m not an expert, just going off of my own experience. I think we have a partial trade deal with a lot of countries, including Japan, UK and many European countries, but not all of them. In the lower tax rate case, I usually count on the tax being in the 7-12% range. For items coming from the Middle East or Hong Kong (and many other countries I’m sure), sometimes I’ve been surprised with a 25% rate for the same items I have been charged ~10% for origin from France, Italy etc.