The axles are out of a 303C that was made by Volvo for the Swiss military and maybe some others. The axles are getting hard to find but there are after-market parts coming out every day. A good price is less than $4000 for the pair. The ring gear is on the opposite side so the wheels turn the right way. They are very similar to Toyota axles in ring gear and birfield size.  I am building this rig for myself and hope to have it done for the next Hammer season.