I've done the calculations for various bicycle gears going uphill, but I seem to have misplaced the paper.
One thing you could try is to keep track of how many calories you consume to keep your weight constant after you unicycle for a specified time compared to when you don't unicycle. Then you can get an estimate of how much your bicycle computer deviates from reality, and, assuming a direct relation between calories burnt on a unicycle vs. bicycle, you can then just multiply the amount on your computer by a certain factor to arrive at a better estimate.
My personal theory is that an average cheap bike calorie counter is more accurate on a unicycle than a bike, BECAUSE it doesn't factor in things like coasting. 443 calories is a lot. That's about 13 or 14 miles of biking.
