I previously did do rapid prototyping in high school and a little bit a year ago. The machine we used was a Dimensional BST in school and in the prototype lab we had a Dimensional DST. BST = break away support type DST = dissolve away support type

Both machines used ABS plastic to print the parts from the CAD file. The quality was superb and worked great for prototype work and mold casting. The parts would not be 100% smooth so for mold casting we would do some minor bondo work.

For the idea you have its ideal, however the costs of the machine outweigh it. If you were to have a place with the machine CAD the part for you and make you a few, sure it will be good but still expensive due to labor/costs. The material is cheap, its ABS for petes sake.