A quick learner from USA says:
April 22, 2016
Hi. Piece that holds the roller is 1" long, 1/2" wide and 3/8" tall. Face is 3'4" wide and 1/2" tall. Thanks for your help.
Paul from SWISCO responded:
April 26, 2016
I'm afraid I've been unable to find your nylon housing and wheel. In situations like this, I have used a self locking wheel with a metal housing. Start by looking at our 87-005. The width of the metal body is 7/16" with a turn out corner that comes out 1/2" to lock it in the window frame. The height of the metal housing is 3/8" and the nylon wheel is coming up to 1/2". Please review and see if this could be a possible solution.