I got a fantastic dress from Primark last month and… it immediately ripped. I’m super sad about it. But while trawling ebay for a replacement (I have not found one yet) I did find a couple of dresses that would be really good for low cost Doctor Who cosplay:
Clara’s Journey to the Centre of the TARDIS dress option:
River’s The Husbands of River Song dress option:
They’re far from perfect obviously, but they’re not bad!