For such a small relative price, you can really improve your system with a newer board; SATA 3.0 verses 2.0 for SSD, faster lower power CPU, better on board sound ETC. Don't get me wrong, I use an i7-870 on an MSI P55-GD80, so I essentially have your old system. And yes, it works really well, plenty well to keep for several more years. But, If my CPU or MB died, I'd go up a notch and get a better MB and CPU for not much more than the old 1156 socket board. I have a SAMSUNG 850 Pro 1TB SSD EXACTLY to move to my next PC, for instance. Oh it's great on this PC, but it will stretch it's legs later on, so I just got the drive I'd get later with a new build.
Even if you get a good deal on an old 1156 MB, and it isn't the same board, you'll need to re load everything (if you have OEM W7 you can't move it, either as the MB ties the license down to that PC). So new windows is needed on top of it all.
So me, I'd upgrade the CPU and MB and use the rest till you can fit a real nice PC together with current parts. It's just so much better long term verses short term to go this way.