The replacement part is not available from the manufacturer but he has the existing broken part that will be relatively easy to copy for someone with basic 3D modeling skills. If you are a 3D modeler who is capable of helping baerfoot keep his wife caffeinated drop him a line in the Shapeways Forums. While you are there you may as well submit your portfolio in the 3D Modelers for Hire section too.
this wouldn't be a big deal to model, but I would never do it. baerfoot should consider changing system to make coffee. there are much better ways to make coffee than with the senseo.
senseo produces so much waste, it is expensive and it brakes!!!