Is there a way to search for G's one way? I ask cos the belief that they are only for overnight flights seems to have starved them out, and blocks out most of the flights I've searched for because no return flights.
Yes it's easy. Just do a dummy booking, selecting "one way" and "spend miles".
The price it shows is for a 100% reward seat rather than for an upgrade, but they both come out of the same bucket.