There was an article on these boats in the March 1984 issue of Small Boat Journal. Here's some information from the article.
20" 10'' overall, 7"9" beam, bottom width of 4"10", a side height of 34" and a weight of 1300 pounds. The boat uses a combination of a outboard well and recessed power tunnel and has no problems with exhaust fumes. The "hydro fins" in the back are stock and enhance directional stability when underway. George Caulkins used the same idea on his Bartenders and called them "spray rails". Do not take them off!!! Neither the Sea Dory or the Bartender will work well without them. The boat is solid glass and extremely rugged. A 70 HP outboard was the preferred setup and gave a top speed of 33 MPH at between 6 and 7 gallons per hour. They were a pretty pricey boat, back in those days. The Sea Dory went for $8K, and fully rigged with a trailer, motor and such was around $15K. The cabin is attached with stainless steel bolts and is removable. Two other simpler models were offered on the same hull (Trawler Dory, Sports Fisher), neither of which had the cabin.
It looks like a pretty neat boat. Lavro built drift boats and smaller dorys for years and they are really bulletproof.
Mike