There needs to be 4 years between the filing date of a discharged 7 and the filing date of a new 13. That means you could file a 13 on 8/27/13. As to the question of, arguably, foreign law and bankruptcy, you might want to consult an attorney who handles Indian law as it relates to the interaction between it and US Federal law.
The answers to these questions may be different depending on your individual circumstance and should not be considered as legal advice or the establishment of an attorney-client relationship.
You can always file a Chapter 13, but you cannot qualify to obtain a discharge of any of your debts unless it has been at least 4 years since your previous Chapter 7 filing. Hope this perspective helps!
Generally speaking, You can file a chapter 13 immediately after your chapter 7. You can either pay everyone 100% of what is owed or you can pay them less. If the refiling is within 4 years, the debt you do not pay, will not be discharged at the end of your plan payments. If it is after 4 years, you can discharge debt. I have no clue on Indian Reservation rights.
This answer expresses only general statements about bankruptcy and/or debt defense and does not constitute advice to you in any form and does not create an attorney client relationship between the party asking the question and the party providing the answer. Furthermore, all cases are fact specific and it is not possible to give you legal advice without a complete evaluation of your case or if you are already represented by an attorney. Therefore, this answer does not constitute legal advice of what you should do specifically in your case. You should seek local counsel to help you with your specific issues.
In order to get a discharge of any debt in your Chapter 13 you would have to file 8/26/13 or later. Otherwise you would be filing a 100% plan. Bankruptcy law applies to these loans made from the Indian Reservations. The history of these loans is that these companies were making these internet loans from out of the country (e.g. from the Cayman Islands or Burma) but when you did not pay and closed your bank account they had no right to use the U.S. Courts to sue you to collect. Somebody figured out that if you went into the internet loan business from an Indian Reservation you could still operate unfettered by State Laws on lending (like usury laws) but, when you defaulted on the loan, they would be able to use the U.S. Courts to file collections actions to recover their debt. Originating a loan from an Indian Reservation does not affect one's ability to include it in Bankruptcy and it will be treated like any other loan. i hope this helps!