It is possible to integrate Dharma teachings into one's daily
life. Every aspect, in fact.
For example, when there are things you can't do for a particular
customer, you explain as patiently and as sincerely as possible.
When he or she lashes out at you, you remind yourself to be mindful
of any negative feelings that might arise in you, and you continue
to listen as patiently as possible to the customer's complaint.
Buddhist practice basically revolves around the core teaching of
'Do all that is good, do no evil, and purify your mind'.
So anything that is helpful to achieving the above behaviour or
outcome, can be considered as practising or integrating the Dharma
into one's life.
In terms of work stress, maybe you can identify what are those
causes of stress and what are the possible ways to reduce or even
eliminate those causes.
If you feel that after trying out many ways and you still find
yourself unable to cope, or from your personal experience, you can
tell that this job will not bring you the kind of satisfaction you
are looking for in the long run, especially in terms of practising
the values taught in Buddhist teachings, then perhaps it is time to
consider looking out for another job.
I wish you all the best.