J.C.
I'm just checking in because I am interested in any answers you may get . . . but I'm really an evangelist about getting rid of any corded blinds after my second son (fearless, and an early walker and climber) came along. I really think he could have been a statistic due to some roman shades if I had spent another couple of minutes in the bathroom one afternoon. I think you are right to be concerned about safety!
It's not what you are looking for, but we did find inexpensive cordless blinds from JC Penney (they just go up from the bottom, though.) If you have an immediate need for a child's bedroom or something, the smaller sizes were under $20/each on sale.