I think Hi-Power and Hi Power are still trademarked by Browning.
So if I were going to guess this will be the Springfield Armory P-35 or P35.
Since neither Wilson nor Nighthawk make their own frames or slides, they would have needed a quality source of frames and slides to do their work. The HP is popular, but not nearly as popular as a 1911. I'll be honest, I love custom BHPs, I've shot several Yost and Novak guns. The MKIII HP is 90% of the way to what those guns are. Only lacking trigger and stippling.
If SA offers a factory checkered version without a magazine safety - and it can be had for <15 bills. I will go out and buy one, perhaps two. Especially because Mrs. RR is a Hi Power fiend and happily approves any and all P35 related purchases.