Mopar 5W-20

For my Galant's first 3 oil changes, I was going to run Motorcraft Syn Blend 10W-30 as this is (or was) the thinnest oil on the market here. Today, I came across Mopar 5W-20 (SM/GF-4) at the Mitsubishi/Chrysler dealer and bought 15 litres of the stuff. I was surprised to see this weight available, as it's all about thick oil here. Thinnest you find is 5W-30. Seeing the same vehicle runs 5W-20 in Southern parts of the US, I don't think there will be any issues running it for 500 km (310 miles) here, before the switch to Mobil 1. Having said that, is this sourced from Mobil or Shell? Thanks!