Kettlebells are great for bodyweight training.
You can use them for shoulder and arm training, and can also hang them off a dip belt to add weight to your dips and pull-ups.
I like the Cap kettlebell because it has a smooth, nice-sized grip, and it’s cheap.
Furthermore, Amazon offers a great price as usual, and it’s also Prime eligible, which saves you another chunk of change if you’re a Prime member. (And if you aren’t, you should seriously consider it. I buy everything I can from Amazon and save a ton of time and money thanks to Prime).