I think dwarf cavendish is the best banana for containers becuase it will fruit in a container. I got mine at a nursur, and have seen some super dwarf cavendish at home depot usually during the summer. You migh want to try ebay. They may be small, or maybe you will see another type of banana on there you like.

I think buying a banana plant almost ready to fruit will be way more expensive than its worth. mne was a 3 gallon for 15 dollars, so a size like that would be pretty ince if you can find one. They probably have them in nursuries in California so if you have a friend or relative (other than your brotehr of course ) whou is willing to look for one, I say go for it, but its going to be almost impossible to find one locally in colorado this time of the year. Most nursies this time of the year are overoaded wit pointsettas!

Maybe it would be simpler to find an online nursery in your brothers area and buy a gift certificate and send to him Not only would you save on shipping it would already be acclimated to his area. And you could maybe send a notice that it is for a banana for his garden. Just a thought.
James

James is right, a gift certificate would be best. Too bad Green Arrow Nursery is too far from Long Beach because they have some banana trees ($13-35 and up). I had bought a 1-gal. container of Williams ($13) and it grew quite quickly.

Banana's grow very swiftly. What ever size you get it is almost more then likely (Under ideal conditions) to reach fruiting size fast. I planted a 1 foot tall Dwarf Brazillian banana Pup that came from my mother tree in June 2009, it's now over 9 feet tall. Also, I can provide insight into purchasing small banana pups, I purchased two from "Leestropicals.com" and recieved them today, they are maybe 3 inches long with no leafs. Both plants were $18 with shipping. They should grow pretty quickly. I myself, purchased Cavendish " double mahoi" and blue java "Ice cream Banana" I've provided a link.
Also "threelittlebirds" I don't know what your climate is, but on another thread I read that "Musa basjoo" is hardy to -20 F. Perhaps you'd be able to grow that. Either way, Good luck.

Here is a link that might be useful: Lee's tropicals