pic above same style switch only a dollar or two.

i looked on ebay and see stupid prices up to $160aud
do these sellers think people are stupid?
below are similar items, you can see price is only a few dollars, may not be same
quality plastic but might be suitable, at least worth a try
a couple of contenders from aliexpress,
up to 125degC for these ones.

https://www.aliexpress.com/item/32737296623.html
or
https://www.aliexpress.com/item/32808829594.html

the water level sensor arrived, looks to me like its very suitable to use with ford falcon,
it will take a bit of diy
Any competent diy person should be able to install it, there is a large nut, some washers and a nifty,
sealing tube that expands to seal as its tightened. Very doable.