Well done Horamkhet.
Sell it quickly before more are found.
You can see from the ongoing discoveries of the sideways inverted 2'6 Aborigine stamp that once people start looking, they will find them.
Interestingly, the 1908 20s Australian postage due stamp has only two known used copies. The first discovered copy sold in 2006 for $AUD60,000 (
http://www.prestigephilately.com/ca...de=austpd)., A second copy offered in the US in 2014 realised just $US25,000 and I thought that was cheap (
http://www.siegelauctions.com/lot_g.../2020&symbol[]=All&lotclass=All&syear=All&pfoper=All&pseoper=All&pfgrade=&psegrade=&gandor=or&keyword=&catselect=eq&pscolumn=default&pssortby=&sortord=DESC&photo=&calledfrom=lkp) but still too expensive for me!
The original sale of the first 1d sideways was an absolute hash and I think the sale price of around $AUD25,000 would have disappointed the vendor given the high initial expectations (up to $AUD150k was mooted).