Gotta be careful about non-KY lubes - Pjur is a popular brand of "personal lubricant" but it reacts with silicone. Not good, even if it is available in quart size bottles.KY works really well. Walmart has their generic version for less than $3/tube.
I don't actually use that much but bought 4 tubes last time just to watch the casher's face.
flots.