Hard question to answer. Here's why:
No 1+ acre lots on McMullen Road are for sale.
No 1+ acre lots on McMullen Road have sold since 2008, and the one piece of land on McMullen Road sold in 2008 was 23.5 acres and sold for 352k.
There were several pieces of land sold in the early 2000's on this road, mostly within in the range of 15-30k.
Hope this is helpful. I work in McMullen Cove and Gurley quite a bit and would love to help you find some land. I know of a few pieces available.
Call or email me: Chris Moore, 256-694-5355, firstname.lastname@example.org