I used to make a simple syrup and add maple extract for my boys when they wanted pancakes and we had no maple syrup (often).
If I wanted a substitute for a diabetic, I'd use an artificial sweetner, not sugar or corn syrup, they are too fast acting as a sugar/carb.
I'd melt some artificial sweetner (splenda or better stevia--you can grow stevia in your gardens) in a little water and add some maple extract.
If you have any health concerns about splenda, read here:
Artificial sweeteners: A safe alternative to sugar? - MayoClinic.com
I like the stevia in natural form crushed, but, it does have a slight 'tea like' taste to it (from the leaves). It's available in liquid forms in some health food stores.
From past experience, sugar free fudge or sugar free jelly bellies use maltitol. That can cause stomach upset and enough gas to power your car. Putt putt putt.
Don't ask me how I know.