I'm assuming you want PayPal, but all I could think is that you want to pay cash.
You can also look into debit cards, prepaid credit cards and "gift" credit cards (similar-ish to prepaid). In the US at least, you can go to most major stores that have gift cards and buy "gift" credit cards for a small fee.
I've already tried though the late pledge manager it simply doesn't give PP as an option. I suspect if you were part of the original kickstarter that had a inbuilt PP option which is no long available.