I just got my latest Hemmings motor news (auto collector news mag). There are usually about 2 or 3 of the big V12 and V16 Cadillacs up for auction - and it is very hard to say what one really brings in today's troubled times. Market as a whole is off by about 1/3 and is not showing signs of recovery anytime soon.
I would think that one of the 1930s era V16 models with an attractive body and good restored show condition would go for about $275,000 USD. Previously owned by da Judge would not mean much of anything to a collector today - Al Capone, maybe - but not this forgotten religious nut.
The really big money in 20s and 30s classics is reserved for the special bodied Packard, Duesenberg, Rolls-Royce, Hispano Suiza and such.
Incidentally, I put up this car (BTW weren't there actually two; the sedan and a convertible coupe?) on the antiques section of my Ferrari site trying to see if it could still be around and have not had any response...maybe time to try that again. If anybody has a picture of the other one, put it up here and I will ask around.