The American Academy of Pediatrics recommends breastfeeding for a year and beyond. I would wait until he is 12 months to wean. I wonder if you may have to do formula if you don't.
If he nurses for comfort, make sure he has another "lovey" to fall back on. Introduce one before you start to wean.
When you are ready eliminate one feeding at a time over the course of a month or so. When one feeding is eliminated, work on the next. This will help him adjust, but should also help you with engorgement.
Make sure you don't leave his favorite feeding for last. You can eliminate a feeding by distracting him. If he asks to nurse, say "Let's read a book!" or "Have some applesauce..." Cover your breasts as much as possible (this is not the time for cleavage shirts!!) so he doesn't see them.
I would really advise against starting a bottle for milk or a paci - these are just new habits to break later.
Good job for nursing for so long and good luck! My daughter was the biggest comfort nurser on record and weaned at 20 months. Now she watches her little bro nurse and has no memories of ever doing it. :)