The little rollers are 1.5" wide by 11/16" wide (outside edge and horizontally across wheel to wheel). The metal attachment piece is 3/4" long w/screw hole beginning 1/4" from wheel mount footing/bracket.
I don't have the top frame apart, otherwise I would send a picture of any interior piece(s) of the roller mechanism. Based upon the single screw that appears to hold this little wheel assembly in place, I don't think any interior portion of the roller guide is needed.
If you don't have the part, and you have a working phone number and/or website address for Decor Innovations for me to seek the part through them, that would be great and extremely helpful (assuming they are still in business...).
Thanks for your assistance with my part need. Kendal