To put in my oar, I was revisiting the same questions as Vanitas about a year ago. I can offer my quick opinion of the Tomenosuke/ParagonFx replicas. I pre-ordered one of the Paragon blasters and after a while managed to get a second hand Tomenosuke "Retailer" 2019 edition blaster which, from everything I've been able to research, was the last/latest iteration of the Tomen incorporating all of their revisions. My understanding is that Paragon outsourced the manufacture of their product to Tomenosuke and my samples of the two blasters bear this out as they are 99+% identical. So if you can source one or the other of them you have a great replica to leave as-is or an excellent base from which to upgrade to your ideal replica.
Dave C
Dave C