I think that your obverse legend begins with IVL, as there is room for it. This bust type is not listed in RIC for Crispus for PTR crescent; but it would be before Trier 425. Though the style looks OK, there are some reasons to think it is probably not official. The most obvious is that the reverse should have three stars over the altar, which are not present on your coin. Since the border is seen, they are not merely off the flan, but not there. So I suspect it is an unofficial issue.