Any suggestions on the most cost effective way to get access to a Qantas lounge?

I’m travelling to the US from Australia in August. I am a Qantas frequent flyer member, but I only have 8000 points. I’d like to be able to access the Qantas Lounge and have read that I can purchase annual access for $500+ which is really expensive for one trip (I don’t plan any more). Can anyone recommend deals or the most cost effective way to get access? Many thanks in advance for your expertise :o)

There are two options I can think of off the top of my head.

  1. Buy a pass off eBay.  Should be around $5o or less. Valid one visit and QF only. So for you that would limit it to Aus
  2. Admirals Club 30 Day Pass.  An old favourite but soon to be discontinued. Last day to purchase it TOMORROW. Not used it myself by a friend has - successfully. Need to Join AA https://www.aa.com/i18n/travel-info/clubs/admirals-club-membership.jsp
Andy