Probably not fast enough for you Aimee, but there's a Cafepress merchant called wayward son (or maybe wayward_son?) who makes Weird Sisters shirts.
Spike's Bitches 36: Did I Sully Our Good Name?
[NAFDA] Spike-centric discussion. Lusty, lewd (only occasionally crude), risque (and frisque), bawdy (Oh, lawdy!), flirty ('cuz we're purty), raunchy talk inside. Caveat lector.
I think he got taken down. I can't find them anywhere now.
Ok. Maybe no Tonks for me.
I was gonna do the Wierd Sisters t-shirt, long tulle skirt, and black combat boots for the Hallows Ball. Maybe some arm warmer's thrown in.
And pink hair.
wibble
What's a "Weird Sisters" shirt look like? Maybe we can make one.
My wife as Tonks? Dream. Come. True.
If it's for Saturday, though, your chances of getting one from CafePress in time are slim to none.
Yeah ... Looks like an iron on is gonna be the way to go.
And I can order another one later.
Watch ... That's gonna be the night I run into people from high school.
If you really really want to, you could silkscreen your own. (I saw a page on d.i.y. one-off silkscreen tshirts.)
There's also printable iron-on sheets, probably available at your local craft store.