I'm extraordinarily fortunate to live near a
quality fabric store.
I went in for a yard of trim to cover threadbare cuffs on a sweater (really, that's all I stopped in for!) and came away with said trim, a new pair of scissors (because I cannot find my regular ones for the life of me), AND ~$7/yard(!) black silk taffeta from a remnant table. I think the latter was marked down because of chalk markings, but those wash off and even if they don't I think there's enough to get a
bongrace out of.
Also, I browsed the trim section beyond my needs and if I ever do get it together enough to do the
hussar/Adam Ant jacket (aside: frack, this showed up on Google), there is enough variety and quantity of gold and silver cords and braids that I might be able to find everything locally.