Hi throughfaith.
God says all his children are his chosen. If Augustine, Calvin, Wesley or barney who lives down the street says that God's children are his chosen then they are just agreeing with God's word...
here's a scripture Magenta posted above.
2 Thessalonians 2:13
But we should always give thanks to God for you, brethren beloved by the Lord, because God has
chosen you from the beginning for salvation through sanctification by the Spirit and faith in the truth.
I think your so obsessed about Calvin that you can't or won't see the blessing of being a chosen child of God. Because of this obsession your missing the point that its not the fact the we believe we are chosen - as all Christians do believe (or should) - but that we disagree on how God chooses who he chooses.