No. Tri-X has always been a negative film. You could get a positive image out of it with positive processing, but I doubt it would look good, especially projecting it, which I assume is what you want to do with the super 8. Positive B&W film is extremely hard to come by these days, as is the chemistry. You'd have better luck processing the Tri-X normally, and then getting a dup of it on reversal stock.