I would not recommend using standard robart wheels on any jet unless it weighs in at less than 11 or 12 pounds, the tires are too soft and tend to "roll" under side loads, although it is possible to place inserts or liners inside the tires to make them stiffer I still found them to be marginal on jet models.
Take a look at Trim Aircraft and Intairco wheels and brakes. They should be much less expensive for you to purchase since they are made in Australia and they don't have to be shipped half way around the world to get to you.

BTW, I have a set of Intairco wheels and brakes on one of my jets and have been very happy with them.