I'm not a fan of crib tents, but then, I've never heard before of a kid this young trying to climb out, so maybe it's a temporary solution for you if you can find one you can afford. Be wary of any used baby equipment, though -- and check recall lists at the Consumer Product Safety Commission web site.
....I will add that once they can climb out it's time to get them out of the crib. I've posted this before but: Put up the side of the crib. Now look at the distance from the top, raised rail down to the floor. Picture your child falling that distance, free-fall, and landing on her head. It's a long fall for a small child. My friend's baby fell from the raised rail and broke her arm at about 18 months and I dread to think what would have happened if she'd fallen on her head or neck. A lot of parents want to keep kids in the crib as long as possible but it's unsafe if they are able to climb out. In your case, though, since she's so very young, turning the bed around or getting a tent may be a short-term idea. Just be ready for her to graduate to a toddler bed or mattress on the floor earlier than most kids!