Ah, do you currently have any old frount derailiers laying around? Try what you have first because I'll bet it works fine. Many old MTB and Hybrids used Suntour FDs with the 110 BDC style crank you're using, so try to find one of those. Almost any old bottom pull 7 or 8 speed MTB FD will work, and almost any older Shinamo road derailer made for a triple crank will work as well (and many of the double units as well). I'm currently running an old RSX 100 unit that works great.
Don't buy a high end new FD. It will cost you money and may not work as well as an old free one.