Yep...I did this too...I was able to fix mine with a piece of the "straw" from a WD-40 can.

Just slip the straw over the leftover stub of the needle and then slip this onto the remains of the needle in the speedo case.

Took a lot of trial and error to get the length of the straw just right...I also put a small dab of glue in each end of the straw to hold it all together.

If yours is a clean break at the speedo with no stub, then I can't help.