It's not covered. So we can award:
1) 1-base by extending the "catch and carry", or
2) 2-bases by extending the "thrown out of play" or the "intentional catch and carry"
I'd vote for #1. While the carry was "intentional" it wasn't done to "trap" the runner (as is the intent of the intentional catch and carry). The "thrown out of play" 2-base award is designed to reflect that runners are (usually) advancing during the throw and the benefit of any doubt should be given to the runner that he would have reached the base to which he was advancing and then the next base on the overthrow, even if the ball had stayed on the field.
Of course, the best option would be to call time when and ask the coach what he wanted. Then, rule on the dead ball verbal appeal.