I'm wondering if 4340 shafts are available for a driver's side drop D44 from a Jeep J10? I'm finding lots of places to get waggy shafts but none seem to be for the wide-trac axle. I'm sure I can have blanks cut to fit but I hoped to find a vendor that had these shafts on stock and would warranty them.
Any suggestions?

Try Dutchman. The outters will fit as they are all the same.

Also try completeoffroad.com

http://eastcoastgearsupply.com/

Give Chase a call. He has very good prices and warranties all his shafts in house.