This app was mentioned in 3 comments, with an average of 2.00 upvotes
What budget do you have? You're presumably not exactly a high income person so I'd just use one of the various smartphone apps (with a waterproof case) and use that instead. They're not as exact as the 'real thing' but the cost saving would be huge.
Another option might be to buy one to 'share' with your club/squad to take out one a week each or something.
Definitely Boat coach. Pretty simple connection with Concept2's Android connection kit and also syncs workouts to your Concept2 Logbook.
Looks very similar to boat coach. Yours looks as good if not better.