Hello jewlsgems ..... Yes your 0.66p approach is the way to go! (lightweight items).
In Australia we can send a C4 size envelope (324 x 229 mm) up to 2cm thick and up to 125grams - for $1.25 (National).
However, sending the same envelope (C4 size) overseas (UK for example) costs $4.50 (International).
Jewlsgems, I notice you've been setting up your store, buying some nice artwork and taking some artistic pictures - good for you. Tell me please, (getting back to the postage thing for a moment), how much does it cost you to send one of your (under 100gram) items overseas, say to Australia? I'd be interested to know...
And as regards that 'hat' - yes, the West Australian sun can be very 'intense' (seems more intense in recent years), but that picture was taken a few years ago now.
Maybe I should 'update' it ...