The idea of a dark suit with bow tie probably appeals most. Can you get away with that? Dinner jacket just seems pointless (hopefully not making a habit of this) but a cheap dinner jacket’s probably going to be less grim than a cheap suit, no?
You might get away with it, but in my experience, the guy in a lounge suit stands out like a sore thumb at a black tie do. And as per my earlier post, even a ‘good’ dress suit is relatively cheap compared to a good lounge suit. So a cheap one from Matallan won’t look out of place – it might do if it’s been worn 4 times a year for a couple of decades, but for occasional use it’ll look great if it fits!
If the hosts have specified black tie, it’s poor form to turn up in anything else.
Maybe try embracing it – it’s actually quite nice to get dressed up in a sharp suit, with a heavily starched dress shirt with stud buttons and a proper bow tie. Get involved, enjoy the occasion, enjoy how good you’ll look, and most of all, enjoy striking the James Bond pose in front of the mirror before you head off out!