Are there any 'Delrin wheel' which can be used general aluminum extrusion NOT from

Are there any ‘Delrin wheel’ which can be used general aluminum extrusion NOT from openbuild?
I’m thinking what is best for linear motion of my next project.

@seemecnc ​ uses some. But I don’t see them for sale on their site. http://cs618717.vk.me/v618717033/ae14/jD85c8h_cDU.jpg

@Eclsnowman , these parts clip over 608ZZ bearings to make the wheels in your picture.

@Eclsnowman @NathanielStenzel Thank you for the info.

@DongWon_Han_DWONH No problem. I wish you luck with your project.

I believe not Delrin, but interesting!
https://plus.google.com/u/0/explore/vcarriage

Never tried them but ran across them awhile ago: http://3d.grabercars.com/