Thanks for those photos, Bo. As you know SBO doesn't allow Boats For Sale ads on the forum. They sells ads for used boats which I think would be effective once you decide on a plan of selling SPRING TIDES. A buyer may come through the forum via the ad.
We can give you our 2 cents here, on how best to go about finding a buyer.
After viewing the photos I was relieved to see the boat has good bones. After 60 years, unless the fragile wood parts (house, cockpit, etc) have received proper care, these boats are often too far gone to salvage unless someone with the means and knowledge will undertake a full restoration. I'd say you had that restoration done in 2004.
The photos of the deck and cabin below show no decks leaks. Very little has been added to the original which is also rare (and good in my opinion). It's a clean slate, mostly restored, ready for a new owner.
I agree with Jon that your lead photo of the moored boat is a downer because of the mainsail. No offense but it sends a bad signal.
This is easy to remedy: Take the sail off and re-photograph the boat, preferably in lower, late afternoon light, with the naked spars. Level the horizon before you take the shot.
First, you're in a good location for an old Alden. I'd recommend looking for a local broker
experienced in classic sailboats. It may even be a broker that specializes in wooden classics.
Price? This is a tough question. There are so few sales and very few comparable boats for sales data. Without inspecting the boat I'd say it's about 85% of a complete, restored classic sailboat. That's a plus in my mind.
A 100% restored and maintained 38' Alden Challenger would probably be realistically broker-priced in the range of,... 40 to 60 K. My guess; the actual selling price would be about 20% less (be ready to deduct the cost of new sails from the asking price).
All in all, your boat is a good candidate for selling but a ready buyer will be the tough part.