The minhag really goes according to two things: your father or your chasidus.
Chabad, for instance, wears a modified bekeshe with one of the corners rounded (at the back split). It also appears slightly different from the other mainstream chasiduses’ bekeshes. Chabad calls it a kapote.
The rest of chasidus, usually wears a regular “suit”, consisting either of a short jacket or a long bekeshe, which they can then go and choose according to the pattern that they like.
Just walk into a G&G or G&B in Brooklyn/Monsey, and they’ll help you find whatever you’d like. There are so many patterns to choose from, and they’d be able to offer guidance. But if you are REALLY looking to put on a bekeshe, think twice, and ask your Rav before jumping.