Do they stock and sell Thompson waterseal

Recommend calling the store and asking for the Hardware department or, better yet, checking out the Walmart app. The app can give you information on what's in stock, the price, and the location of the item (aisle #). (Some items may not be updated right away, but it should still give you enough info to help.) Best of hopes to you!

And

Yes they do.

I do not know.