Stay away from SBA. There is a saying about SBA. If you have the credit for it, you don't need it. If you don't have the credit for it, you can't get it.
What is your FICO score? If you have EXCELLENT credit as you stated then a low interest personal line of credit may be your best option. I'm interested in seeing if you understand (not an insult) what excellent credit means in this economy.
You say $20,000 more... How much have you already invested and does the existing business have sales or a track record? If you are saying it's your friends and a subsidiary, I'm assuming it's internet based. If that's the case I think the term you are looking for would be "white label".
I'm interested in talking with you though. Even if not to invest, I'm always interested in how people are making their money and getting it. Let me know that above info and I think i'd be better able to help you on how to finance your project.
When I stand before God at the end of my life, I would hope that I would not have a single bit of talent left, and could say, "I used everything you gave me."