I’m wondering if you could help me. I just moved into a new place and it’s an old building. I’m having trouble finding gliders to fit the curtain track that’s already here. I’ve bought 3 different kinds and none are the right thing and I’m struggling to find fit. I’m attaching a picture of one old glider that was still in the track. If you could let me know what it’s called or where I might find something like it I would really appreciate it.