A pet door for vinyl sliding doors is usually thicker than a patio pet door made for aluminum sliders. If you have vinyl sliding doors you will get a better fitting pet door panel if you choose one that is made specifically for vinyl. At the same time pet doors for vinyl sliders are almost always designed for optimum energy efficiency with features such as dual pane glass.
Ideal dual-pane insulated VIP vinyl patio pet doors are available in two different pet flap sizes that are very common so they may work for your dog. In addition, Ideal now has a vinyl patio pet door model with single pane glass and it is quite affordable. If you live in a region with a mild climate you should take a look at Ideal's single pane vinyl patio pet door.
Hale's OMNI panels for vinyl sliders come in 11 different pet flap sizes - more sizes than any other brand. If you have a very tall or very short dog you will find the right size in Hale's OMNI lineup. All OMNI patio pet doors feature dual-pane glass.