Do you mean Asphalt Kits? The cardboard drums that asphalt comes in?
What Type are you looking for Type 1, 2, 3, or 4? Most roofing supplies carry type 3 (Steep) ASTM D312 Type 3
If you do not understand type, you are in over your head. This stuff is heated to about 450 degrees F to mop, it is nothing for anyone who is not a professional roofer to fool around with. It will burn the livin hell out of you.