IIRC Investment Arms barrels come from Italy and Italy has some of the best barrel quality control of any country. Some of the Cableas guns are made by Pedersoli (also Italy) and they are extremely high quality......usually.
IMO it would be hard to go wrong with either brand. Im not a big sidleock fan but IF i ever buy one it will be the Cabelas Sporter Hawkens carbine in 54cal. While not a true traditional, its a nice big boomer.