Need to store a password, cannot use hash

Application has many users, some have accounts on a third party site.

Needing to programmatically access and scrape a the third party site. It has no API or key based auth.

So I've got to either:

• Ask the user for their password to the third party every time we need it. Not really an option as user will not always be present.
• Store the user's password to the third party site.

It pains me to ask, but what's the most safe/practical way to do this? I understand there isn't a completely safe option here.