I know I can't really help with this thread by commenting, but I have two from the AU breeder (I'm local to them in Brisbane, QLD, AU). $550 AUD for the first one 6 months ago but they'd been that price for years and for the second (purchased a fortnight ago) I paid $660. Free delivery as the gentleman who owns the company delivered them to my house for me.
Mine would be the siblings or at least 'related spawn members' (assuming that multiple females spawned). From the research I've done regarding the person who originally owned the wild adult broodstock there was only one large spawn 5.5 years ago.
Shows what a difference that the feeding regime makes. The ones being purchased now (My 2nd one, Toad) are still only around 26cm, so UNDER 1ft in length. My 2st one (Tadpole) who was purchased 6 months ago is now 35cm so has finally broken the 1ft mark. Can NOT WAIT until he's a big boy like yours. =)