@Stan Galat the wheel diameter is 2 1/2 inches. I dug around for the smallest wheel on the smallest inline skate I could find in my garage (sorry, Lexi!). I considered grinding it down a bit (just as JMM (Michael) and IAM-RAY suggested), but after a quick dry fit I just decided to go with the wheel as it was. Works great, although I am a bit curious about IAM-RAY's 'quad' skate wheel suggestion. Those wheels are wider and flatter, correct? Seems perfect! My wheel doesn't cover the entire back of the pedal, but is very solid and smooth feeling (far and away better than the original mechanism). And as I previously mentioned, the most interesting coincidence is that the standard inline wheel bearings fit perfectly on the VW axel pin! Super easy and quick to make the swap from the original plastic roller.
@ZFNHSN my car is a VS, and on the CocoMats site there is a drop down selection for 'replicas' when selecting make and model of vehicle, and you'll see the various replica builders listed!! Pretty cool!! The mats fit perfectly, and are absolutely top quality, btw.