p. 544-545 of John Houchins' L.C. Smith "The Legend Lives" has a price and grade comparison for Smith and Parker guns 1888-1941.
p. 546 has a grade comparison for Smith, Parker, Lefever, Fox, Ithaca and Baker guns.

Probably should not scan and post unless someone can find other sources for the comparisons. I did not find the list on the LCSCA site and did not check the PGCA site.