Some other possibilities:
Peer-to-peer lending - just listened to podcast 29 or 30 (?) and the limit was 30-35k. I dont know if that is still accurate.
B2R financing (or any asset based lender) - an asset based lender may be able to fund this if you were to show all the business plan stuff
Kickstarter or more likely Kickfurther - Kickfurther is something like a phase-2 crowd-funding. A lot of companies request money of varying amounts on here to take their business to the next level. Returns for investors are 6-12% for 3-12 months. This is a pretty short time-frame, so I'm not sure how that would work for what you need.
Kiva - They do give out loans for Americans.
Apply for a grant since you are a non-profit. Either through the government or a NGO. Expand your target audience to qualify for more money.
Ask your current landlord for a loan.
Partner with a good burrito restaurant. Burritos + climbing = goldmine!
I like @Troy Fisher's idea of the self-directed 401k: gives you equity in an asset.
I wouldn't worry about pitching the idea of a gym. How many gyms does Boulder, CO have per capita? People love climbing in a good gym.
I'd be interested to learn how you started up your first gym. PM me if you feel up for sharing.