There are quite a few long-term cruisers staying in the Rio and I would try to contact some of them to take a look at the
boat for you.
Try this forum. Getting
marine supplies and
repairs there is possible, but it will take some time and effort. There are also quite a few cruisers-turned-boat repairers who can help out. However, you will need to be careful to make sure all the paperwork is legit and you can get all your ducks in a row before leaving so that you can clear out of the country, enter
Belize and/or
Mexico, etc. It's not a bad trip up to Florida from there, via
Belize and
Mexico, but it does require skill at tropical piloting, dealing a bit with the usual officialdom, and some planning in terms of weather/currents/etc. Isla Mujeres in Mexico is a good last stop before making the 300+ mile jump back to the U.S. It is not like cruising in U.S. waters. The
charts aren't accurate, a lot of the guidebook information isn't much better, you can't count on things like buoys or lighthouses to be there or working, etc. If you have sailed in the
Bahamas you will find that eyeballing the shallow areas is not as easy down there. The worst problem in my opinion is that the harbors along the Mexican coast north of Belize are few and far between, not well sheltered, and offer poor or non-existent holding ground until you get to Isla Mujeres, which is a fine harbor. Or maybe you plan on heading south to
Honduras and then
Panama?