probably not that easy to sell. most people who want to keep and have the resources to keep aros I would guess want to raise them from small themselves rather than buy someone else's almost adult that had outgrown a cramped tank. not many people have empty cycled 300G tanks just lying around ready to accept those fish. and if they have several of them in a pond I guess their worry would be if the new fish had any diseases or was incompatible with them from the aggression standpoint.
then you get into the shipping issue unless you can find someone local but that's a small chance. trying to ship a 2-3 foot fish whilst keeping it alive, temperature controlled and not dying of deoxygenation or ammonia poisoning in enough water is going to be a huge challenge/very expensive.
even my LFS who actually sells them dissuaded me from impulse buying one for my 180G because they said it would be quite difficult to rehome once it was fully grown. i'm going to wait I think until I can afford at least a 10x3x3 or a pond setup. so my recommendation is don't do it with your current tank.
then you get into the shipping issue unless you can find someone local but that's a small chance. trying to ship a 2-3 foot fish whilst keeping it alive, temperature controlled and not dying of deoxygenation or ammonia poisoning in enough water is going to be a huge challenge/very expensive.
even my LFS who actually sells them dissuaded me from impulse buying one for my 180G because they said it would be quite difficult to rehome once it was fully grown. i'm going to wait I think until I can afford at least a 10x3x3 or a pond setup. so my recommendation is don't do it with your current tank.
I think the aus ones will move easily enough, like others said depends on your area. Even a black would probably sell well. Silvers get drop eye, are extremely common, have a low initial investment and it doesn't become more valuable as it grows.