Only second-hand, if available. But there's plenty of pre-used, pre-sewn fabric. You just need to reimagine it from a dress or shirt into whatever else you're making. And you can find the occasional old button box, but they get snapped up fast.
I saw some fabric near the curtains and sheets, but if you need a lot or something specific you would have better luck at g street fabrics a few miles away.
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