The oil doesn't matter, just use what you've been using (as long as it's not synthetic). None of today's mainstream oils have the right amount of anti-wear properties for a cam break-in anyway, so that's where the break-in additive comes in. The Lucas break-in additive is a decent one and is found at every Oreilly here, and probably available in your area too.
http://www.lucasoil.com/products/display_products.sd?iid=82&catid=9&loc=show
Tip: Mix the additive with the oil BEFORE pooring it into the motor. No need to take any chances of the cam not getting the right amount of zinc because it hasn't mixed yet.