I must confess to being "out of my league" when it comes to wines priced at the mentioned range, but I think that you want to be on the look out for the private label stuff that is made in Argentina for various retail/supermarket chains.... Also, may importers/distributors do 10-20L runs of lots of inexpensive Malbec and put them in a nice bottle and push some hard promotions..... also, Kirkland may have something in this range.

Else, go to your local wine merchant and have them look up their database... if you buy by the case, Im sure they will even special order for you...

A quick Google search found the link below, but please check the details as I have no idea how dated the selections and prices may be....
http://www.momtastic.com/food/171449...ines-under-10/

Happy Malbec Hunting !!!! ^