Every duty free shop at LAX sells wine, but it is for a high price (typically double the Trader Joe price for the same wine, sometimes triple), and generally cheaper to buy wine upon arrival at SYD (which offers duty free upon arrival). Tequila is just about the only thing I've found sold at LAX duty free that is cheaper than at SYD, so kind of pointless to carry it with you just to pay more
But if cost is a factor, cheaper to buy from TJ even with the cost of an extra checked bag fee (if you buy enough); for example TJ sells excellent Monopolowa vodka for $10/litre compared to triple that price in the duty free shop for the same quality.