Some of them that have caught my attention:
I've been taking a look at some of the suits from e-haberdasher, but I want to know your opinions. Also, how much should I be looking to spend?
All of the brands you mentioned are a good option. Benjamin suits are a great value. I definitely recommend ordering one and trying them out. Great customer service, good people and product.
What do you think would be the best benjamin navy option on e-haberdasher? I'm 17.5 on shoulder width. (36R/S-38R/S)
Doesn't look like they have your size, but this one http://ehaberdasher.com/index.php/designers/benjamin/benjamin-sartorial-suit-navy-5431.html