First---Welcome to the forum.
I think you will be able to handle that trailer. You will close and marginal, and you might have to upgrade your truck a little. Meaning going to a heavier tire. That will help with carrying the weight plus it will get rid of the squeamish feeling back there.
Make sure you have right set of WD bars and a good hitch.
There should be others here that will offer their advise and experience also.
Now, remember one more thing.
That dealer would more then likely tell you your tow rig would handle it 100% even if you had a ford ranger. All he wants to do is make the sale.
Don't get in a hurry and don't get caught up in the excitement of the moment.
2008 Cruiser CF26RK
2013 Ford Eco-Boost
Heavy duty payload - Max tow