black dress with sleeves cocktail Dylan & Davids Elegant Lace Midi Short Dress, Women's Formal Party Dress, Size: 3XL, This dress features a flattering wrap design that accentuates the waist Elegant Black Mesh Short Sleeve

The main reason I shared this one is that its got such nice long sleeves

Or, if you feel like staying at home first, and have 1950s housewife skills, maybe whip out the sewing machine and a stack of vintage sewing patterns, so that you can create a unique retro formal dress style

A woman would be banned from entering a restaurant or dance hall if she dared to wear pants (which several Hollywood Stars tried and failed to do.) That being said I think you could wear nice slacks with a 40s top and be perfectly well dress at a 1940s party today

Plus, with your wedding shoes on, the tailor can adjust the hemline to the correct length