Yes a reptile enclosure would be ideal.
It all depends on the size of the snake. If you are starting out with a baby snake then I would get something of appropriate size. As the snake grows so should the size of the cage. In my opinion the appropriate size for an adult boa is at least 11 to 18 inches high X 4 feet wide X 6 feet long. Many breeders keep their full grown females in much smaller cages with no ill effects.
Sometimes your local pet shop or better yet a reptile shop can offer you with asistance
Good luck
If you have any more questions give me a call at (408)981-6694 so we can have a more effective conversation.
Brian
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Brian Gundy

www.for-goodness-snakes.com