I pay for stuff once in a while on PayPal. However, I do not maintain a cash balance with them, nor do I have a linked bank account. I have only my American Express card linked to my account.
A few years ago, I ordered some dirt cheap magazine subscriptions on eBay. I had done the same on eBay once before without a problem, but that was before the scamsters caught on.
You see, there is an inherent vulnerability with magazine subscriptions: they are not expected to start serving until approximately eight weeks after you order them. That's plenty of time for you to give positive feedback and a crooked seller to make more sales. It's also beyond that 45-day window you mention.
In the event, a couple of months passed. No magazines. I checked the magazine subscriber service sites and found that no subscriptions had been entered for me. I had paid on PayPal, via my American Express card. The action I took was to dispute the charge on the Amex website. It didn't occur to me take up the matter with PayPal first, so I didn't run into the problem you had. In any case, the chargeback was resolved in my favor.
Not long after that, eBay stopped allowing subscription sales on their site.