I need new "KILIAN" rollers

These rollers are from Klein patio doors that are about 40 yrs old.

The wheel width that fit in the track (outer to outer) is 11/32" as best I can tell and the entire roller is about 1-3/4" diameter. I have 6 of these doors and many rollers are worn. The have both steel and nylon rollers. The nylon rollers are stamped KILIAN-Toronto-Syracuse. If you think I can replace the rollers themselves could you tell me how to get the axle out of the wheel?

I though maybe you'd have to drill them? I'd prefer the entire assembly but will work with what I have to. Thanks for any help you can give.

I can't say for sure, I've never seen this roller either, but you should raise the possibility that the axle may just push out.
It looks very likely to me.
In a pinch I've used a 1/4" socket under the bottom and a punch to force the axle down through the roller into the socket.
I would also worry that the original axle may be the perfect length and the replacements may not be.

Thanks for the advice on the axle,very much appreciated. I'm a little worried myself with the age of these that I may make the situation worse by tinkering. I'm wondering since I'm having such a hard time finding replacement rollers if I bought the large replacement track cover if that would improve the existing rollers. Some of the rollers are loose/wore at the axle point so I know they need replacing but the ones I took the photo of are in decent shape. If I can get at least some of the 6 doors working better I have the option of not using the others. Again any advice is appreciated.

I can see some wear on the track from the point between where the rollers actually touch and where they don't but it is even wear, not roller coaster as I've heard some describe it as. So I guess that wouldn't be considered damaged then?