Bruce
TVWBB 2-Star Olympian
I don't have a Lowes near me, but this might help someone else out.
slickdeals.net
Extreme YMMV - Lowes In-Store - Weber Replacement Grates 17.5 in Cast Iron ($21.24) and 26 in Stainless Steel ($16.97)
Please don't thumb down, as I doubt these are clearance nationwide, but you never know. If you are in your local Lowes, its worth looking if you are in need. Also, I couldn't find the price