416,

I was thinking about this overnight. As you don't cast, presumably you don't have a lubrisizer so you can't even buy gas checks and put them on the bullets yourself. I checked the Lee catalogue and they don't do one of their standard bullet sizers in the right dimensions either, although they will make you one I believe.

Your best bet is to find someone with a lubrisizer, borrow it and buy the right dies (not hugely expensive) so you can gas check the bullets yourself. Otherwise you could sell the bullets to someone else and start again. Sorry but that's not much comfcort to you.