I don't think there is another guide out there. Wish the guys who made this one would correct it, but the problem is PSA has slabbed so many incorrectly I don't think they are admitting to it being botched anytime soon.
Example:
https://goldinauctions.com/1923_New_...-LOT23876.aspx
Says 1923 on it........problem is its a 1924
This example was initially wrong and they have since corrected that (on years 1923 to 1928), but that was corrected before their guide came out and once it came out they have yet to fix any inconsistencies on years after that so hard to trust the 1930's.
Again so many have been graded its just a mess, it would be nice if they or someone more knowledgeable then me came out with a corrected guide.