Alternative to 1" threaded low profile headset?
Can you take replacements for the stripped parts from a standard headset? If you have a local bike co-op or a good relationship with your LBS you should be able to try some second hand ones to see if they work, and if so either buy them or buy a new headset and use the parts you need from it (in that case leaving the extra parts with the shop is a nice gesture, and they're more likely to be useful to another customer than to you)