set options in scope of a `source`ed script

I'm writing a shell script that sets enviornment variables. It will be sourced in other scripts like

source /path/to/my-script

I want my script to use set -euo pipefail but I don't want to affect the calling script.

This will affect the calling script.

# my-script
set -euo pipefail # affects the caller
export VAR=$(get-value)

If I wrap my script in a subshell the export won't work

# my-script
(
  set -euo pipefail
  export VAR=$(get-value) # not exported to the caller
)