I'm not sure how this idea would work.
Back in BC, I was a member of a volunteer search and rescue organisation. Training was paid for, as well as expenses for tasks and traveling to training out-of-town. As well, unlike other SAR groups in the province, ours was one of the few with full funding from the regional district, so we had all the toys. Unlike most other SAR groups, we did not have to fund raise. The only things the individual had to supply was their clothing and personal gear, and their time.
In spite of all this, it reminded me of my time in the PRes. Our group had close to 100 members on paper, yet only the same dozen or so members actually showed up regularly for practices and tasks. Other SAR groups with less funding had the same problem of retaining dedicated volunteers.
The few people with higher level training (e.g. search managers, team leaders, etc.) burnt out fast because they were needed to assist other teams, and because they needed to work more during their own time to perform administrative functions for the team.
If the volunteers were paid at least an honorarium for their time, would we have more people showing up? I don't know. Or maybe people didn't like getting calls at 6 pm on a cold, wet November Sunday evening to go look for a lost hunter...?
The PRes had pay, and we were hard pressed to field a platoon. The SAR group had no pay but all the bells and whistles, but we would still have to call for help from neighbouring teams that were not as well equipped because we either lacked the numbers or the needed people with special skills. I think it boils down to more people having less spare time, or less willingness to devote time, to serve in these types of teams.