350$ is around the average price I see on Morph Market for one. There's a couple as low as 275. But sometimes I think an established snake is a bit nicer than a fresh new hatchling.
Given that this one is breeding size, I don't think that's a bad price at all if that's what you're planning on doing. Cutting out the raising up part. Could ask if the noodle has already been proven as well.
Even for a pet and not for breeding, you don't need to worry about moving up in tank size as much as it will already be a larger size snake.
Also.... there's the 'ooo' factor. Sometimes you just see a critter and know it was meant to be. Regardless of if it's a little higher or not.