A Philoshopical Question
I am not sure you are in a conundrum. Certainly there are very inexpensive, lightly built boats that would suit the purposes of someone interested solely in day sailing in protected waters. But being boats...they are not exactly cheap and you could still spend 50k.
Sailing in any waters, you want a boat that is very seaworthy, well built, that will give you confidence. You will likely want a boat that can handle going to weather when a blow comes up and you want to get home...even if home is just a few miles away.
I would submit that there are plenty of seaworthy boats that I would term "offshore capable" for around 50k. The question is more what is an appropriate boat for you and your needs. How much boat can you handle, what kind of rig is best (ketch vs sloop), and what kind of cabin layout would you like below. Also, what kind of boat appeals to you...shippy looking, traditional or euro modern. And what design is best for your needs, a heavy full keel boat or a more modern underbody.
Age affects people very differently. I do not know what you can handle. I do know one couple just in the 70''s that are out there kicking butt racing a Wauquiez Hood 38...a 22,000 lb displacement sloop rigged sailing MACHINE.
And as to the question of crew...I would not think it an issue. Its probably best to get a boat you can singlehand even if sailing as a couple.
Perhaps you could post a little more info on your sailing experience and skills. That might enable some folks here to respond with some good suggestions.
Hope this helps