binding barrel bolt meets a carriage bolt

[cropwell]

It would help if you could give us an idea of what you are trying to achieve. I respect that you may not want to disclose the end use, but some indication of the forces involved may be useful. Also is the axle to be free to rotate in the yoke or must it be definitely fixed? Are you looking to scale up to produce many units, or are you making just one or two? What material is the roller? Will it be wet (aqueous), oily or dry in end use? Do you have a unit cost limit in mind?

If you wanted a quick bodge you could pop rivet a length of tube into the yoke.

BTW cm is not a preferred unit in engineering, metric users prefer mm. In the US they use inches a lot (but not excusively). Some of the Model Engineers in UK use imperial measure, while some of the absolute recidivists use Furlongs, Newtons per square fortnight, Firkins and Ducats per gross. Oh! and BA screws.