cb11,
I was right where you are now on the 8th of July. The problem is not finding a peg that will fit the hole, thats easy enough.
The Kawasaki pegs "pinch" against the back of the mount for rigidity.. Alot of pegs are made to "pinch" or hold the peg in the bottom of the mount. I could have made something work but the other problem was, once I had a bigger, thicker peg in the stock location, my wife's boot heel on the peg it forced her foot back towards the saddlebag even more.. she could mount and dismount easier with the bigger peg.. but wouldn't tolerate her foot and calf pressed back against the bag.
Thats why we made the 1.75 in extender.. with the Givi E52 mounted .. she has a good comfortable pillion space sitting back her hands resting on the bags, her legs in a more relaxed position.. she says she can use her leg muscles better for braking, her knees not bent as hard...
Hey if thats all it took to keep her happy after me hyping this bike for the last year... only to get it.. fall in love with it.. and on the way home have her scream in my ear... I hate these pegs and seating position.. You gotta do something about it.. or I'm not going to New England.. I liked the old bike better..wah wah wah wah wah.....

sigh.
Sometimes necessity is the mother of invention..
Anyway... thats how I stopped the whinin... and went to New England happily..
Hope this helps you,
Jerry