Screen door roller replacement

Hi. I am looking to buy a few replacements for my screen door rollers. I attached pictures of the unit I'd like to purchase, and I am writing to see if you might be able to help me find the correct product to buy? I have no idea of the original sku, etc. I would like to buy several, so I have some backups for the other wheels as they deteriorate. Please let me know if you can identify the correct product, and if you sell it. Thanks very much for the help!