MAX158 Digikey Part # MAX158BCPI-ND $22.63 MAX158ACPI from Maxim site $25.42 MAX158BCPI from Maxim site $18.62 MAX154AENG from Maxim site $32.67 MAX154BENG from Maxim site $23.63 74125 Digikey Part # DM74LS125AN-ND $0.64 Jameco Part # 46501 74LS125 $0.35