Dragonbox Pyra.
Not sure how soon you need it out what sort of browsing you will be doing, so a Pandora with a USB wifi thingy might work. If that isn't good enough I use an e-ink ebook reader from several years ago for a bunch of books, including comics, however mine doesn't have a web browser or wifi. For general use on the go I use a laptop or smartphone.
If none of that is suitable for you without an additional purchase (I try not to buy things unless they will be heavily used), I suggest getting the cheapest one that checks all the boxes for you. Do you have a preferred OS or specs? I vote for buying used, and would suggest an older X series ThinkPad tablet version, as it will give you some flexibility and you can probably get one cheapish.