Direct replacment ignition coil?

Hello everyone, it's been a while, and it's good to be back!

I've been up to a lot, I have 3 new tractors, been building a tractor shed, and doing school.

But here's me recent dilemma. (fyi this may not be the best place for this thread)

I got a 1978 Sears 18-6 (as big as you can get a lawn tractor), with an 18hp Onan twin. I'm not getting spark. After a careful series of careful deduction (sticking multimiter prongs into random holes), I debated that I need a new ignition coil.

Now here's the thing, it's an Onan. A used ignition coil on ebay runs between $50 and $100.

So I'm curious, If I get some different ignition coil, like this: http://www.ebay.com/itm/Gravely-Tractor-Lawn-Mower-8163-T-Onan-B43-16HP-Engine-Ignition-Coil-Not-OEM-/200984830002?pt=LH_DefaultDomain_0&hash=item2ecba12032 With new plug wires, will it still work? Can I just plug any coil in? Maybe even run two single coils?

Thanks for any tips fellows!
~BM88

Since it's a 12v powered ignition system rather than a magneto, you may well be able to run two coils in parallel. I think at this point, I'd hit CL or a junkyard, looking atbike and ATV coils. What comes to mind immediately is the coils from my old Honda motorcycles (Shadow and Interceptor)- and many others. These coils provide spark for two cyliders at a time as well. They look like a normal bike coil would, but have a plug wire coming out both ends instead of one.

These coils run a waste-spark system like I believe your twin does (the Briggs do). In a waste spark system, one spark is generated and sent to both cylinders simultaneously. One piston is on the compression stroke, one is exhausting. It is easier and cheaper than implementing a distributor system for such a small engine.

Ahhh that makes sense.

The thing is, my current coil has two other plugs on top (not the plug wires), one from the batter, and one to the points.

From what I saw, bikes have only one input wire.

I think I'm going to but the one in the link above.

That essentially comes down to + and -. Some bike coils are mount-grounded, some have two terminals.

I was able to purchase that coil that I mentioned in the original post! Sure hope it works.... But I only paid $10.50 so it's not that bad.