Are there 3D models of the Infiniium UXR-Series oscilloscopes?

Yes, see the Step format file downloads in the Technical Overviews below.

For 4-channel 3.5 mm input oscilloscopes, see: http://www.keysight.com/support/UXR0334A

For 2-channel 1.85 mm input oscilloscopes, see: http://www.keysight.com/support/UXR0702A

For 4-channel 1.85 mm input oscilloscopes, see: http://www.keysight.com/support/UXR0704A

For 2-channel 1.0 mm input oscilloscopes, see: http://www.keysight.com/support/UXR1102A

For 4-channel 1.0 mm input oscilloscopes, see: http://www.keysight.com/support/UXR1104A