Welcome to the forum, Lynette!
I believe your Outback has a tow rating of 2700/270#, which is great for the type of trailer you are seeking. I think you are wise to leave some margin in your target trailer
weight.
Under 2000# with a bathroom pretty much means a 13’
Scamp. My suggestion would be to make the deposit for a new
Scamp as a backup and start looking for a used one. There is a steady trickle of used front bath Scamp 13’ers in the used market. Be prepared to travel. Scamp’s deposit is 100% refundable if you are able to find something before they start your build.
The 13’
Casita Patriot Deluxe is another option, but it will likely push your 2000# target. It runs a bit heavier than a comparable Scamp.
Casita discontinued that model in 2015, so used is the only option.
Shopping used your may find an occasional 13’
Trillium with a front bath, and maybe a few other uncommon models I’m forgetting, so do keep your eyes open for other possibilities in the 13’ class.
We love our 13’ Scamp. It’s the simpler front bunk version, which includes a storage compartment for a small porta-potty. Pull it out and use it in the trailer, or they make tent-like privacy units you can set up outside. If that could meet your need for a toilet, you have a lot more options.
Best wishes in your search!