Shower door rollers are offset by 4cm - is this normal or has someone bodged it?

Our shower door seems to be a bit of a bodge, or I’m searching for the wrong thing as I’m trying to replace the broken wheels on the top and bottom runners.

Simply the top wheels are on an attachment which extends from the top of the shower door, isn’t inline with it but is infact 4cm above where the bolt goes through the door. This seems to mean most roller fittings won’t fit the door.

Can anyone recommend a replacement roller that’d fit this kind of door? I’ve searched amazon and various other sites but nothing has come up yet (UK, if that matters tho right now I’d order internationally if something worked).