The cool thing about bearings is they are standardized AS FUCK.
Those on that link you put have metal seals so they will end in 'ZZ' (rubber seals are 'RS')
If you can get yours out and read the actual bearing number on the outer race, I bet you can buy a sleeve of them for the price of one from a speciality house.
The trick is to get the bearing number and buy a Timkin, Koyo, SKF, or FAG then never have to worry abou tit again.
What is that black thing on the bottom? If it's a lip seal, they are just as standardized as bearings when it comes to numbers.
Also, don't repeat that or tell anyone. I kinda want to corner the marking on ''Grand National roller bearings''. lol