What is the issue with them being none powered?
There is no issue if the first 2-3 is not powered. The power draw from your motherboard will be sufficient to power at least 2 without having to need additional power. For example, if the motherboard supports triple SLI/Crossfire, it will no problem power 3 cards on 3 unpowered risers.
Also, price update. For $10 a piece now!