I do not separate my HPR kit from the model rocket kit I use the same field box as we normally fly rockets types together items marked with a * are for HPR only and items marked # are for model rocketry only.

Field Box...

At least this is what I have in my field box...

1. Swiss Army Knife: for all kinds of things.
2. A pair of slip-jaw pliers: for getting motors out of the rocket, aid in cleaning up RMS casings.
3. A modeling knife: for those unexpected precision cutting & trimming jobs.
4. Baby powder: for powdering the parachute to make sure it deploys properly and doesn't stick.
5. Extra Igniters.
6. Extra Wadding. #
7. Sandpaper: for cleaning ejection pistons, and for helping motors into model rockets.
8. Superglue: for those fins occasionally dislodged by a sudden stop at the ground with model rockets not HPR.#
9. Epoxy Glue for on field repairs.*
10. Silver Foil: for mixing epoxy on.*
11. Cocktail and kebab sticks: for mixing epoxy.*
12. Masking tape: good for shimming parts to fit tighter, also good for taping on the launch rod like a little flag to hold the rocket up off the pad for model rockets (to avoid Bernoulli Lock). You can use spent black powder motor casings for this with HPR rockets.
13. Cellophane tape (Scotch tape): for taping two-stage motors (booster & upper stage) together on model rockets. #
14. Electrical tape: in case of launcher repairs.
15. Straws: for replacing lost launch lugs on model rockets.#
16. Extra shock cord for model rockets/#
17. String in case of a swing test after a field repair of a model rocket.#
18. Sun Block: time flies when you're having fun - before you know it, you're a crispy critter.
19. RDF TX.*
20. RDF RX.*
21. Yagi antenna.*
22. Quick match fuse: For cluster engined model rockets.#
23. Spare batteries for model rocket launch controller, Bleepers, Timer, Altimeter, RDF TX and RDF RX
24. Spare crocodile clips for launch controller igniter leads
25. Thin Flat screwdriver for turning on and installing timer and altimeter.