I don't care what someone says in regards to what boat "used to be on there" - that means nothing. We need to find out what the trailer is officially rated for, which will tell you if the frame, axles (and that tilting mechanism), etc are rated for the 'wet' weight of your boat - which you need to figure out.
From the picture, it appears that it is a non-braking model. What are the laws in your state about that? For example, in PA, any trailer that is rated for 3,000lbs gross or more (gross included the weight of the trailer) MUST have brakes on ALL axles.
But, let's assume it's properly rated for the amount of weight you would need and that it's just an illegal trailer (from a braking standpoint). It's a "keel roller" trailer - they can be a real pain in the butt to load as you have to make sure the keel of the boat stays perfectly centered on the keel rollers - otherwise you're scraping the keel on the trailer frame. In reality, this means you'll be completely rebuilding the bunk system. And, you'll have to add, I'm sure, brakes to at least one axle to be legal. By the time you're all said and done, you'll probably have (including tires/lights) somewhere in the neighborhood of $1,200 to $1,800 invested in it... on top of the initial cost. In my book, that's a "no-go".