Hello Drover
According to
This MSDS Mechanix Caustic Soda is >98% purity so that should be fine.
Coogee Chemicals is correct, there is only one manufacturer of methanol in Australia. Make sure it does not say methylated spirits because that will not work.
Bottom line, it should disolve. Make sure you keep stiring it because in my experience if you leave it sit the NaOH will form into a solid lump similar to concrete on the bottom of the container. Has it done that?