Fogging Oil equivalent

Hi Chris - are you wanting  a corrosion inhibitor??

If so you might consider Valvoline Tectyl 506 which is readily available in Australia (I know cause I live just south of you).

https://www.valvoline.com/en-au/tectyl-506-heavy-duty-rust-preventative/

https://www.tectyleurope.com/wp-content/uploads/2019/01/PI_Tectyl-506_TE031-01.pdf

I have used Tectyl for many many years - its a liquid wax that can be thinned (turps/GP thinners) for spraying (can also purchase as an aerosol but costly). Dries to a wax finish that is self healing (flows into scratches), is extraordinarily persistent.