First things first, your options and price point are severely limited on Amazon but it is doable. Second, the vape envy is going to exist no matter that you get, vapers are always dreaming of their next setup. Just get a simple, basic starter kit and get use to it and vaping before worrying about more exciting and advanced stuff. Take that time to research and learn to better make the decision for your upgrade.
That being said to stick around $50 this is probably your best bet.
http://www.amazon.com/mini-protank-Mini-Protank-Blue/dp/B00GSHLU8K/ref=pd_sim_auto_2
The only issue is I doubt you are going to find much quality juice on Amazon but there are some to get your started.
http://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3Daps&field-keywords=E+juice
If you can I would order your juice from mtbakervapors.com as they have great prices so you can try a few without spending too much.