http://www.plbrentals.com/

The cost is $54 for a week. It will arrive in time for the SHF or HMB or whatever offshore race you want to participate in. They will give you (in advance, but you have to ask for it) the Beacon ID, sticker, etc. information so you can complete your entry. Rental includes a Post Paid envelope for returning it to them when you are done with the race--just like Netflix.