500 keys @ $.35 = $175
500 keys @ $2.00 = $1000
I think that's where people feel slightly uncomfortable. I have to be honest, I feel the same way. I understand where you're coming from but the risk is very minimal on your end and the profit margin is too large. Its true that you're fronting the money, but I don't think anyone wouldn't in this situation. Even at $1 a key there would be a very small risk.
The argument that people can just buy these and flip them is true for any group buy. I mean look at the original prices for the GB that was actually suppose to happen here. We paid $.51 cents each, there was no stopping anyone from amassing 100 of them and selling them for $4-5 each. The difference here is that it seems like you're the one flipping them now (I'm not trying to accuse you of this, that's just the way that it appears). And the big problem with this is you're the only person with the keys! Unlike in other group buys, where people amass keys and risk resell, you're running a monopoly on these, so the risk is even smaller. Obviously if you were to sell them closer to at cost, you should put some sort of limit. The interest seems to be high so even if you limited people to 10-20 keys I don't think you would have a problem selling them.
I would much rather prefer if someone helped you out and organized an opportunity for people to buy these from the original group buy, up to the limit of the original order. Any extras would be up for grabs. Since you don't have the time for this maybe someone could help you out? I wouldn't mind, and I think other members would be willing as well. There is still quite a bit of time before the actual keys from the GB come in, at least a week maybe longer, so I think there is more then enough time for someone to work this out.
Anyway, I guess those are the feelings that I wanted to voice out and for you to understand. In the end, I won't judge you in any way whatever you decide to do. I myself would happily buy a few keys for $2 a piece. I know there would be some unhappy people though, but you organized the group buy, this opportunity landed on you, so whatever you decide I'm on board. And in the end, you buying them and making a profit (again, not accusing you of doing this) is better then some random members doing it. This is your GB after all.