Maybe think about a water bed pump for the res change, they are electric and generaly under $20.
How is the quality build of the cab? I read all the threads on these cabs on their web sight about 3 months ago and have found that allot of people have problems with the heat, and that is funny especially when their big bost about these is that they are sapposed to be the "Cool Cab", but what can you do. Glad you are making the most out of it.
Adieu