Compare the average fleet+rank pay.
The figure for 2019 FO 737 was AU$199,000
Today that would be significantly higher with the yearly pay scale increases.
I'd really be surprised if you found any 737 FO's averaging less than 65hrs, if not 70hrs per 28-day roster.
No chance you can get away on MGH of 53.4. You'll get nabbed on your AV days.