Green Aura, why would you
buy one? They are really easy to grow:
1) Eat an avacado, (preferbly organic

)
2) Wash the stone
3) push a cocktail stick into each side, about half way up, just far enough so it'll take it's weight
4) sit it on a bottle or jar of water with just the bottom 1/4 in the water
5) keep the water topped up & when the roots fill the jar,
6) pot into mulit purpose in a large pot
7) pot on when it out grows the pot
8) when it reaches 2M/6ft (ie after about a year) give to friend with two storey conservatory!
Or flog on a well known interweb aution site to those who don't realise how easy they are to grow
Of course it won't be on dwarfing root stock, but I reckon the bonsai route should do the trick; my mate's really dinky bonsai apple produces tiny apples!
MW