Ken,
According to Tom Archers excellent articles on SAC in Double Gun Journal Volume 14 Issue 2 Summer 03 page 128:
00 grade $28
0 grade $30
2 grade $40
3 grade $50
"Grades 0 and 2 were identical to the 00 grade with the exception of barrel steel."
"The 00 grade was the plainest and cheapest gun in the product line, being fitted with blacked fluid steel barrels called "triplett steel"

The SAC guns are cool.