Ranger 23'''' $3500??
This is one of my favorite boats of this size and era and an asking price of $3500 for one in the condition you are descibing is reasonably priced. (I would expect to buy the boat for something like $3000 or so) You really did not discuss the condition of the sails and that is an important point since the sails for a boat in this price range can equal half of the cost of the boat. If not scratched the hull might simply polish out rather than need painting and so you might try a test patch. Depending on how much rust is on the keel bolts this could be more serious than you realize. You do need to get this boat surveyed because as good as these boats are, they are getting long in the tooth and can have some pretty expensive ''issues''. Of course that is true for nay boat of this age.
Now for the bad news, while this is a perfect boat to develop sailing skills, it is not a boat that I would consider suitable to make the trip from Texas, around the coast all the way up to Canada. It can be done if you pick your weather window carefully and you are a good sailor, but the lack of space, storage and weight capacity of a boat this size makes a trip like this pretty hard going. OTOH I guess if I had to make a trip like this in a $3000 boat this is not the worst choice.