Dear Sir,
Thank you for your request.
Regarding basic (=obligatory) Swiss health insurance, you can find a comprehensive comparison tool with all health insurance premiums here on moneyland.ch.
There is no special discount for partners in the Swiss basic health insurance. Your premiums are dependent on where you live, your age group, if you need accident coverage or not, the insurance model and deductible you choose.
Be aware that Swiss basic health insurance premiums change once a year - the premiums for next year will be published on moneyland.ch in October.
In the comparison tool, you can find not only the premiums, but additional customer satisfaction ratings of 2017 (for Avenir, which belongs to Groupe Mutuel, too).
You can find additional information on various health insurance topics here.
Best regards from Moneyguru