rue21 is cheap and always has cute dresses but they aren't maternity

Amazon there r many like this one ссылка

Not sure where you can look I'm thinking a place like Dillard's or a department store like that. The best thing you can do is probably do a search for an empire waist dress which will work best being that far along and it may not need to be maternity necessarily since empire waist dresses are pretty forgiving and you'll have the extra length.