HI Bruno,
You are not going to find any IBM provided SSL Certificates for TM1 versions that are out of support.
The way to proceed here is to generate self-signed certificates - your InfoSec team should be able to do this.
There are various articles on the IBM site regarding this but they will obviously not relate to v8, v9, v10 or v11 (2.0.x) as these are all out of support and sunset.