I read your post at least twice, and it seems to me that you are definitely concerned with the cost potentially involved in "invoking SAR." I don't now why, as there is typically no such cost, especially in National Parks. There is a provision in NPS regulations that provides for charging for rescue operations - this provision is invoked only in cases of incredible, Darwin Award-like activity (usually the individuals have violated safety closures, or left an apple pie on their table in grizzly country, or something similar). Your group is a long way from that situation.

Which National Park will you be hiking in? Although the expertize in SAR varies from Park to Park, usually depending upon the environment and demand, nearly all, if not all, of the larger National Parks have rescue teams that are highly competent. Yosemite and Grand Canyon would be mentioned any time you are trying to determine the most such competent group in the country. Many, if not most, local jurisdictions have highly competent operations, with the particular advantage that they are fully aware of local terrain and conditions, something your support group may lack. This is an extremely important factor in SAR operations.

Anytime you are breaking out ropes for high angle rescue, you need an experienced, practiced team. Actually, the same is true of stretcher carries in the back country. Even if you are using a wheeled stretcher (a Stokes or something equivalent), carryout can be exhausting and difficult, exposing both the victim and the rescuers to injury and complications. The best use for an improvised stretcher is for a short (quarter mile or so) carry to a helispot. Carry out for any distance measured in miles will be very long and tough, unless your victim is exceptionally light. This never happens. The victim is always the heaviest member of the group (a corollary of Murphy's Law). The time involved in implementing makeshift measures often triggers a cascade of circumstances which can quickly turn a routine boo boo into a life threatening emergency

The equipment you carry should be commensurate with the knowledge and skills of the group members. If your leaders are skilled at high angle rescue, they know what they will bring. Gadgets and toys without the experience and skill to use them are just burdensome extra weight, as a previous poster has adroitly pointed out. Good SAR gear is heavy.

You are obviously thinking carefully about this trip. If only more National Park visitors did the same. I take it for granted that your group has decent first aid skills. You would seem to have communications covered. Apply them if necessary. Practice prevention and avoid unreasonable risks. Have fun and if SHTF, don't worry about finances. There are far more important considerations, like saving lives and minimizing suffering.

Hey, that's a good idea!

-Blast

I think for the most part, I would agree on the responses you have received to date on potential significant rescue/medical issues, so I think I will try and give you some ideas (although you have covered several yourself already) on what I would suggest your backup responders might have with them when meeting you to take care of moderate issues.

Water and food
Cooking Set/stove and fuel
First Aid supplies to backfill what you may have used during the trip to date
Extra blankets and/or seeping bags
Tarps
Rope/cordage/paracord
Lighting devices: flashlights, lanterns, batteries and/or fuel, strobes
Matches, lighters, dry kindling, fire starters
Duct tape
Hiking poles/staffs
Cell phones, additional radios
Various sized or backup clothing
Jackets/coats/sweaters

The thread linked below illustrates my concern regarding the financial consequences of a SAR effort that might be invoked by my Scouts:

Found, rescued and billed $15,000

My concern is the gray area between "We intentionally incurred unreasonable risks" and "We made a really dumb mistake and need help".

Given the possibility of a $15,000 charge for going off trail and then getting injured, I have directed my hiking crew to use the '911' feature only in a life-threatening situation. That leaves the responsibility of responding to a 'HELP' situation to the support team.