Now all is gone except a VIP V2 Bed
The only chance at a direct Paypal link is when you complete the order. At the end there is a big PayPal banner that will link you directly. If you opt to not pay on at spot at the end of the initial checkout, then you have to do it manually because there's no other screen that will link your order directly to PP.
In the menu on the left side of his site you'll see "PayPal Guide". Just manually send the funds as "goods" to that address there and include your order number in the notes