The following are in stock and apply to the 20% off full priced toy sale on now at David Jones, some of these are available cheaper elsewhere but it is the cheapest I can find Luke's helmet online for at the time of writing.
75327 STAR WARS LUKE SKYWALKER (RED FIVE) HELMET
75304 STAR WARS DARTH VADER HELMET
75328 STAR WARS THE MANDALORIAN HELMET
75305 STAR WARS SCOUT TROOPER HELMET
Was $89.95, with 20% off is $71.96 free delivery with all orders over $50
Thanks OP