I always thought that a notary just 'testified' that they witnessed you sign your signature and that you provided some identity that you were you, or that they personally knew you. They do NOT swear as to the validity of any statement made on the paper.
How could they? How could they KNOW that you got the money, or whatever it says.
They can't, so the statement always says something to the effect of "sworn before me this xxx day of yyyy".
So, there are certainly templates online, but I'd just go with your own handwritten bill of sale because the vehicle title is the main thing. But, a bill of sale should include:
Seller's name (printed),
Seller's signature,
buyer's name (printed),
date,
purchase price,
Vehicle year/make/model and VIN #.
And some statement to the effect that this is for "paid in full"
Kirk