In 84, the bucket seats changed in the Suburban to a reclining seat with armrests.
In 87 the bucket seats on the Blazer/Jimmy changed to a top and slide setup. The 2 share the same mount spacing AFAIK.
Pre 77-87 hi back buckets from a Blazer/Jimmy are going to be the same seat as a 77-84 bucket for a Suburban.
If you were able to get the seat tracks from the 89 Burb were you not able to get the seats also?