Pete, I've been thinking of selling #916 to free up some garage space for something a little more exotic. I'm located off exit 46 on Southern State Parkway. PM me for my phone number if you want to see it. I think it's nicer than the one you looked at and the price is in the same ballpark...
134 is the build number, not the Festival number. Two different things.
As with any older car, mileage and condition are important in determining the value. Some people may think Festival Cars are more desireable.
The number written in marker behind the rear plate was the number assigned to the car at Indy. It is not the build number. All TTA's have a build number; only Festival Cars will have a Festival number.
Festival car
Your build number is somewhere around 130; it is most likely a Festival Car. LotusS4 on this site has alot of the Indy signout sheets. He may be able to verify it is a Festival Car and tell you who drove it.