Found an inexpensive source for additional compartment (basement storage) door keys.

http://www.amazon.com/gp/produ...i_detailpage_o00_s00

Not sure if this link will work for you. If not, go to Amazon and search Southco E3.
These fit my '92 Breakaway 30'.

No "cutting" necessary. Mine fit as delivered. However, the handle part of the key (the portion of key you grasp with your hand) is a little large. I had to grind a little off to enable the key to be turn without hitting the door lift handle.