Museum Replicas, the famed (and somewhat pricey) provisioner of well-crafted replica Medieval, Renaissance, Viking, and fantasy swords, armor, clothing, and apparel, have leapt heedlessly headlong into the alternative 19th century realm of steampunk. Currently, they have some clothing and accessories, a few weapons, and a couple steampunkish gadgets. Their catalog is small, but I suspect it’s just a “feeler” to see what the market is really like out here.
If their sales are good, I image they might expand their catalog, but be warned: Museum Replicas is known for their premium prices. Still, their Feromonic Field Detector Ring or the Steampunk Aether Monitor might be worth a look. They also carry a few of the exorbitantly priced WETA rayguns.