According to the data plate in your other post you need a 6206 and a 6205 bearing. You can buy them with shields or seals, won't make a difference if your motor is totally enclosed, data plate says uniclosed but I don't know what that is. I would get the bearings with seals myself and you take out any doubt about the frame.
I would go to a bearing supplier...maybe Motion Ind. and buy SKF bearings, ignore the country of manufacture they're good bearings, and they shouldn't cost a whole bunch. The SKF numbers would be 6206 2RS C3 and 6205 2RS C3. 2RS means a rubber seal on each side and C3 is the internal clearance of the bearing.
If you think there is excessive clearance in the end bells use GREEN sleeve retainer to hold the bearing in the end bell. Green is designed for this application, Blue, Red, and Purple Loctite is designed as a thread locker not a sleeve retainer. To be exact I would use Loctite 641, it will fill a .008 diametral gap and can be disassembled without heating should you need to replace bearings in the future.
I also wouldn't worry about greasing the bearings in the future, they'll last a good long time especially if there's no radial load on them. Just be sure to pay attention to the way they sound while the motor is running and change them out right away when you hear them start to fail.
We have 20 HP motors at work on a shot blaster that run sixteen hours a day with about 50 pounds of weight on the shaft at 3600 RPM and they haven't been greased in three years and they are running strong yet.
Confidence: The feeling you experience before you fully understand the situation