You could cheaply reach the same altitude using a helium balloon. 121,000 ft is only 37km. Plenty of home grown helium balloons have reached that height (and higher).
$200 to $300 depending on how much you scrounge from people. I spent more because I decided to do my radio ham qualification in parallel and buy some gear for that.
Most of the gear I used in the capsule was cheap (camera from eBay, Arduino, strip board, polystyrene box). Paid real money for the balloon, parachute and helium.
EDIT: As the parent comment was deleted: this was in reply to a question asking about the approximate cost of something like GAGA-1.
My project reached 32km: http://blog.jgc.org/2011/04/gaga-1-flight.html