Is there a VIN on the motor that should match the vehicle VIN?
Yes there is.
http://www.toyotaparts.metro-toyota.com/ENGINE_SERIAL_NUMBER_LOCATION_T-SB-0301-08.pdf, I added this to your previous question, the serial code location is given in the link above, the serial digits should match the last several digits in the VIN.
If they don't match -run away fast! It could be a salvage vehicle (rebuilt after an accident with junk yard parts and who knows how competently OR it could be a stolen vehicle. Probably not what you want to hear, but a good deal is not always a safe deal- Good Luck on this.
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