You can use an exacto knife for the rehairing tool (replace the blade with a needle that you've cut the end off)
- lot's of spare needles, slightly larger seems to be more durable.
- glue gun for gluing the hair in (low temp gun is good and less damaging)
- wire to pull the tail into the pony (some people use fishing line)
- zipties (both small and large to secure the tail
- hemostats are great for removing hair
- last but not least hair
I think that about covers it