Unusually, both Coles AND Woolies have cashews on sale at the same time.
Coles are slightly cheaper, price equivalent to $12.50/kg, but Coles only have salted cashews. Woolworths have both unsalted and salted on sale, same price, but 750g instead of 800g.
Woolworths Unsalted: https://www.woolworths.com.au/shop/productdetails/202399
Woolworths Salted: https://www.woolworths.com.au/shop/productdetails/172660
Neither of these prices are as cheap as last time, but I reckon those were unicorn events.
Comparing the cashews from both stores, I find the Coles cashews to be better cleaned, the Woolies ones often have traces of husk still attached.
I can confirm that the Coles offer works in-store, I just went to my local Coles and purchased some.
Be careful not to accidentally pick up bags of mixed peanuts and cashews, which are usually right beside the cashews, and often get mixed in with the cashews.
Allergen warning from Coles:
May Be Present PEANUTS, May Be Present OTHER TREE NUTS, Contains Cashew, May Be Present MILK, Contains TREE NUTS, May Be Present SESAME, May Be Present SOY, May Be Present CEREALS CONTAINING GLUTEN
Don't take these to school kids.