I wish it had a more generic part number so I could swing by an oreillys and ask them to see if they have a part in stock.

It does… Part # 121g Tell them you're looking for a part and you have a part number. When they ask for the number tell them 121g

While you're there get some elbow grease to lubricate and seal the reservoir after topping up your blinker fluid.

This was their April Fools' Day joke back in 2020 [1]

[1] https://aprilfoolsdayontheweb.com/joke/20200297/

Why do they need a disclaimer about it being for "entertainment only"?

Kinda takes the fun out of it. You already can't buy it on there.

To make it clear incase a younger customer stumbled upon it and didn't get the reference and prevent any spurious lawsuits maybe. It didn't take any fun out of it for me.

Also a clueless collector might mistake it for a serious prop.

"Rated to 1.21 Gigawatts? We're gonna test that."

and now it's gone :)