Well, for starters, it's never actually said that Ijaat embraced the Mandalorian ways of his father (in fact, the fact that he disowned his father is an indication that he likely did not, though the fact that he did it in the Mandalorian way counters this somewhat). There are also no canon appearances of him wearing armor, much less pictures. Just my 2 cents, but I would say making the armor would probably be ok (it looks like it meets all the criteria) but you wouldn't be a canon character. It would be considered your own creation. The armor looks awesome (I really like the low-contrast look in particular) I just don't think it would be considered canon.