I would also say that exporting to scale to PDF or EPS or printing to PDF would be the easiest way. To create a 'to-scale' raster image is also possible, but it is more complicated, and you will have to go through an image editor:
in SU, create a parallel view. Draw an empty frame with known dimensions round your model. export an image to a high resolution. Open the exported image in Photoshop. In Photoshop, crop the image to the frame you drew. If your background is uniform, you can use the Trim command Resize the image to the dimensions your frame should have on paper and to the desired final resolution. Now, if needed, you can crop the image further, when you save it, it will retain its dpi value so that it will get placed to Indesign to the right scale.Anssi