My budget is below $1000... Yikes.
I found a used Jupiter DiMedici on eBay, it seems to be in good condition, but I'm afraid to risk it. I also found and Armstrong but I've heard mostly bad things about those.
My band teacher also recommended that I get a flute with open holes and a B foot.
OK, now we have something to work with. There are a number of good options around the $1000 price point. eBay can be a good place to get a flute for a good price, but no matter what the seller says about the condition, expect to spend about $100-$500 to put it in top playing shape. eBay can be risky too unless you are VERY familiar with the market. Some sellers sell junk and there's no way to know for sure until it's yours. So, buyer beware...
Used flutes are also available from a number of reputable flute dealers. so check out some of the online stores listed in the Fluteland FAQ. It also has links to some of the best flute vendors that are online along with recommended brands and explanations of flute features. Be sure to check it out!
Also, I did a quick search of a few stores and here are a some new intermediate flutes with the features you mentioned (open hole and B foot) and in your general price range. The lower priced ones will be silver plated but some may include a sterling silver headjoint. Be sure to read the specs carefully before you buy.
https://www.flutes4sale.com/collections ... dizhao-300
https://www.flutes4sale.com/collections ... dizhao-400
https://www.flutes4sale.com/collections ... -model-665
http://www.jlsmithco.com/750-1500/trevo ... ge-p3-rboe
http://www.jlsmithco.com/750-1500/trevo ... -p3-rboe_2
https://www.kesslerandsons.com/flutes-p ... te-flutes/
I hope that helps. Do a little more research and feel free to ask more questions!