The 5HP Briggs is an excellent choice on minibikes and is used on many. That is a tidy looking Briggs with low hours, but I don't believe it is considered a raptor. That is a stock water-pump motor, but most, if not all raptor parts and aftermarket parts would fit that engine.
Now, since that is a water-pump unit, there is a high chance that the output shaft is not usable for a clutch, so a different crank may be needed.
That engine looks to be an early 2000 model or late 90s. :thumbsup: