Hi Dennis, i am "in the same boat" currently using a duct taped tiller (would not longer lock.. so i taped it up).

it is an arriba fiberglass expandable. cost $144 (largest size)
many people use ACE or HomeDepot paint sticks but i hear they splinter (or get fiber glass in your hand)

you can look at murrays.com (or here i am sure) to see what is out there.

i used to use the aluminum ones on my h16.. but i broke my last one and have switched to the more solid feeling arribas (cant say they are any better).

my friend uses the carbon/fiberglass combo arriba stick.. it looks and feels nice but is $250? the full carbon one is $350...

I think a bit pricey for a stick