Northern Blue tongues sell out fast. The Indonesian localities can be found, but those are typically wild-caught animals, which can come with a host of issues. A $150 Northern would be VERY hard to find. Minimum price is usually $250-$300. And to clarify, there are no Northern morphs in the US, there's just different variations from line breeding.
As for the setup, I agree with artgecko. Ditch the red/blue light - blue tongues are diurnal so you just give them regular light in the day. Basking spot is good for them at around 100°. I don't use UVB and neither do many breeders/keepers. The like to burrow so that's good to provide. 40 gallon is considered absolute minimum. You'll want something bigger, but it's ok for a baby; they do grow fast though.
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