Can't be done. They don't exist anymore. I've looked everywhere and kicked myself for not buying the 2-pack from Costco a few weeks ago. I checked Costco, ToysRUs (sign in the window: no sleds), Target, Wal-Mart. I decided rather than traipsing around to more places I'd look it up on-line. Sold out, everywhere, unless I want to wait a couple weeks. Snow is coming tomorrow, can't wait a couple weeks.
Today I figured it was time to get creative so I went to Lowes. I looked at heavy duty floor mats. I looked for large round flower pot bottom things (you know, so water doesn't run all over the ground), I looked at metal tubing to see if it could be cut to something useful, I looked at rubbermaid box tops, I looked at trash can lids and found something that I figured would work pretty well but I didn't need the $17 trash can that went with the lid. Up and down aisles, seeing bathroom things I'd like (oooh, a rounded shower door! French doors for the deck! a storm door for the front! and this way cool stuff for the kitchen counters, a do-it-yourself kit to resurface countertops).
And then I found this. What do you think, will it work?