I take it you're talking about the launching trolley jockey wheel rather than the road base. it was an extra for us - we bought it direct from west mersea trailers after a few months struggling along without one.
You can get the jockey wheel for the launch trolley direct from Laser. Just go onto the website and order over the internet. They deliver within a couple of days.
I didn't get a jockey wheel with my Stratos - didn't even know they provided one until I read the Y&Y boat test. Then I visited the West Mersea stand at the Dinghy show to price one up. They were surprised and said that they were 'standard' with the Stratos combo trailer and referred me to Laser. The boat had to go to Laser for some warranty work on the gelcoat, I mentioned the jocket wheel at the time and they provided me with one at no cost.
Do you mean the jockey wheel with the trailer or the launch trolley? The jockey wheel on the trailer is standard but the one on the launch troley is an extra as far as I am aware.
The jockey wheel I received from Laser was the one with the hinged handle. Both the road trailer and the launching trolley have jockey wheel sockets so I move it between the two.