In case anybody is interested, I found a company that rents PLBs. I don't know if we can post links, so just google "PLB RentaL" and it will be pretty obvious.
It's $39/ week, it says on the website that they charge in one-week increments, but the lady I talked to said that they can also charge by fractions of a week.
If you don't know what a PLB is/does, when activated, it sends a data burst every few seconds to the Search and Rescue Satellite (SARSAT) constellation, which in turn is sent to the Air Force Search and Rescue Coordination Center in Virginia.
The PLB has a built-in GPS receiver and sends your location in the data bursts, so the rescue coordination center knows your location to a high accuracy.
You can also buy one, the basic models are almost $300 but don't require a subscription, but they also don't do anything but tell somebody that you need somebody to come and get you.