Hi Gil. It's good to hear from you again.
You can set this excerpt as a slight variant of the format for an accompanied solo. You can include any dynamics and other details in the "solo outline" line. You don't need to use the orchestral format, so no marginal abbreviations are necessary. If the information that it is for trumpet in E-flat and orchestral reduction is not included in the introductory text, you can put that in a TN above the excerpt. I think the term "orchestral reduction" clearly implies that it is for piano.
Glad you're back on the job.