I wouldn't go the 700 route either, but I know he likes to keep it cheap.
Another good option for building a 4l80e is a guy in Akron - Vince Janis/Janis Transmissions. Probably cheaper than Rossler, stands behind his work and will go through it after he builds it for very cheap. He is known for building 200-4Rs, has a full weight 86 t-top GN with no cage that runs high 9s with a 200.
I use him for all my builds.