Tough one. If you want to sell altogether, you just missed ponycon! Wouldve been a great way to sell all.
Advice? Either wait til next ponycon, 'cause no-one outside of the UK is going to pay the postage for all of them, OR split into individual sales, one by one. G3s don't sell too well, so it's best to get PCs for any you're not sure of. My G3 sales didn't go so well, but good luck to you!