Design help needed

[Scott McKie]

Hello,
I have an electronic R&D project and have run into the following problem:
I need to drop +120 vdc to +12 vdc; 300 mA current, and can not find anything on how to accomplish it except for a step-down converter that puts out a -12 vdc output.
How can I change the output to a +12 vdc with the 300 mA capability?
Please help either with a fix for this problem or knowledge of another setup that can accomplish the voltage drop.
Thanks