Use bike grips, and if they're too big wrap hockey tape around the area you're putting the grip on and keep wrapping it until when you put the grip on its snug. Sorry if that made no sense I'm stoned right now
so i just made mine yester day and i shimmed it with some tubing i found lieing aroung and it worked perfect what you want to do is make sure you have atight fit on both the pole itself and the bike grips take some gresse and a heat gun and warm up the tube to slip over the pole and let it cool to make sure it is on tight then get a stap or shoelace. (what i used) then take a smale screw and screw the lace onto the pole after that cut a small hole into the grip and run the lace though there and then place the grip onto the tubing while pulling the lace though and there you have it!
I a cut strips of o bike inner tube and glued to the pole then just glued the bike grip to it, I also but a small bot under the grip as they started to slide down a bit after about 10 days of use.
for the strap and bar end, buy a wooden rode that is the same internal diameter of the pole then glue that in to place. I used the bar end the came with the grips and cut the piece that sticks in to the handle bar off and drilled a hole in it then you screw both the strap and bar end to the rode in the pole. I used straps off rental poles which are easy to get at my resort
These have lasted me one and a half seasons so far.