The bracket is going to look something like this but they’re usually sold with the rollers. If you want just the brackets you might have to find out the manufacturer. I’ve had to track down some rollers for pocket doors in my sister’s house from the ‘50s. Fortunately they were still in business and the lady I called had some new old stock lying around. She sent them to me for free because she said she wouldn’t even know how to charge me for these old parts.