Hi George, any decent hardware store should stock better quality sandpapers and reckon your local Mitre 10 might have some of these assorted grits that come in a pack of 15 for $2.00 - https://www.mitre10.com.au/sandpaper...pk15-buy-right

If you want better stuff you can order online from The Sandpaper Man as this is where I have bought the micro mesh guitarist kits from...https://www.thesandpaperman.com.au/micro-mesh-kits/

The micro mesh kits come in handy for the final finishing off once you have completed all coats of finish. In fact it would be handy to also get some 1200, 1500 & 2000 wet & dry sand paper for doing the sanding between coats and these grits are also the ones to use leading up to the first 4000 micro mesh pad.

Hopes this helps in some way.

Cheers, Waz