There are solo Trumpet and Trombone below, beyond that the Iowa Orchestra you will find above should meet your solo multi-sample brass needs. It contains Trumpet, French Horn, Bass and Tenor Trombone and Tuba. They are generally have two or three velocity layers and roughly every note sampled. What you won't find are articulations beyond basic sustain. The trumpet does have true vibrato sustain and the WIPs scripts add in scripted vibrato and legato. If you want to disable the vibrato or legato, go to the appropriate tab and hit disable.
The Sonatina also has solo brass, but it tends to be one velocity layer and every third note sampled. With this limitation in mind, it does sound quite good. Mattias Westlund did an amazing job getting the brass section (and the orchestra) to sound coherent.
For ensembles you can try either the Iowa which is scripted, but has more notes / velocity layers, or the more natural Sonatina which is more lightly sampled, but does have two velocity layers for some ensembles and has the staccato articulation.