I think we've been through this whole thing many times but basically you need a dealer who is AECA registered, and there are very, very few of them.
The ones I know of are Leroy's Big Valley Gun Works in Montana, ETSS in Colorado (who charge a lot), and of course Questar.
The application process they go through is this:
http://www.pmddtc.state.gov/docs/oas.pdf
And it's that and nothing else. Anyone who tells you otherwise is wrong (including US dealers, some of whom are still living in the stone age). That's off the State Dept. website.
On the Canadian side the guns need to be registered (phone up the CFC, they will refer you to a verifier for restricted firearms in Ottawa) and you will need an IIC from DFIAT. The exporter needs a copy of the IIC to support the export licence application.
Then they package up the gun and attach the export licence and ship it to you via whatever carrier they use, or they can hand it over at the border if you want to go down there and they want to go up there. And then you have to get CBSA clearance, which means they assess duty and GST and have a look at your registration/PAL and ATT.
How this works depends on how you've done it, you'll get a call from the broker to come down to the CBSA office and present yourself for example. If you've done it via a dealer they have to go and do this, which is what they're charging you for. Once it's cleared you get your package, either shipped to you or you can pick it up from their depot, the dealer or whatever.