Intelli-Shop currently has 700+ phone & web shops. If you're not signed up with them, I'd urge it.
Have no idea how they pay. I mean, whether it's worth it.
I have had shoppers say, on this forum, that they can earn $30 a day doing phone shops. That would easily meet your monthly goal.
IPSOS has literally hundreds of phone shops. You must be a customer of the specific bank, but they pay $15 per call. I think there are limitations/restrictions on these calls, so I'm sure you couldn't do one or two every day.
The Source (was Trendsource) pays miserably for phone shops.
Once, a couple years back, out of desperation, I signed on for phone shops. I worked over 100 hours, and made $35. I was really, really bad at it! I mean, I stank. Totally incompetent. And I had over 10 years of experience msing!
So best of luck.