what is the best sleeping bag i can get?

Any sleeping bag would work as long as you're appropriately dressed. I found some affordable sleeping bags from Modell's Sporting Goods for $10.

Coleman sleeping bags are the best because they keep you safe and comfortable in the outdoors. The are also very durable. It splits into two single sleeping bags. The Coleman 8041-949 Hibernation 40-Degree Two-Person Sleeping Bag is a comfortable three-season rectangular sleeping bag. At 66-inches by 75-inches, this bag can sleep up to two and fits most body types up to five-feet 11-inches long. With six pounds of Hollofil-808 insulation, this mild-temperature sleeping bag keeps you warm in temperatures down to 40-degrees Fahrenheit. Features include a cotton cover and cotton flannel liner that are commercial-machine washable, an exterior pocket, and the ability to zip two like-bags together when sleeping with another.
Coleman Colossal 20-Degree Rectangular Sleeping Bag (Super King) is also a great sleeping bag. It:

• Keeps you warm in temperatures down to 20-degrees Fahrenheit
• King size (39 x 81 inches) fits most body types up to six-feet, four-inches
• Cotton cover and cotton flannel liner, commercial-machine washable
• Five pounds of Hollofil-808 insulation

When you are outdoor you can sleep comfortable in a Coleman sleeping bag. Have a good night's sleep like you are really at home.