Depending on where you are in Sales (what field, your position) you may want to either stick with the black, white, and navy traditional looks or you may even be expected to show a little more style. In a conservative environment You MAY be able to get away with some pastels depending on what your bosses wear and if they look good on you, but probably only on an accessory like a small scarf or hankerchief or if it's very subtle maybe your shirt (under your jacket). In a less conservative environment like for example any place dealing with art, fashion, or younger customers you could probably get away with wearing more color and wearing suits and cuts which are a little more fashionable than traditional.
You'll almost never go wrong if you wear
something like these three pictures, since traditional styles are that way for a reason, but it also might not hurt you to go for something
more sharp if you wear it well.
A last note: Definitely take a friend with an eye for this kind of business fashion with you if you go thrift shopping again. I hate to say it but people will absolutely judge you for what you wear. If it LOOKS like it came from a thrift store, or like its polyester, that's going to hurt you. The general rule of thumb is dress like the person whose job you want. Even if you don't want your bosses job it helps if you "fit" (but not copy) the style they set.