If you try bending it back upright it may break. Even if it doesn't, it's weakened.
I actually put a bank of 4 carbs on a bike, where one of the carbs had only 1 post -- I ran into the same issue, stuck float pivot pin in one of the posts, and I'm really ham-fisted and busted it off.
Bike ran fine. Had one of the 4 carbs with only 1 post.
But I got lucky. I have seen others try a '1 poster' and the float didn't turn the gas off and that one carb leaked out the overflow.
If you can, replace it with a good solid carb body -- good peace of mind. These old bikes we ride, they already have a fair amount of breakdown or breaking risk even if everything's ship shape. The more things I can eliminate the less risk of a breakdown.
I got stranded once on a fine-running Kaw 400 triple. It was a low mileage very good running, good condition machine. The throttle cable broke. Bunch of miles away from home.
One other reason I like to replace with solid parts: when I go to sell the bike, I don't have to disclose a repair, and I can look the buyer in the eye and say 'no hidden issues'.
It's just me, personally, wanting the bike to go to the new owner the way I'd want to buy a used bike -- as little risk of a failure somewhere as possible.
I can't speak though to the microwelding, don't have experience with it, for all I know it's real solid.
