@USO-Josh, instead of doing another run of MST-100's, how about making a limited edition batch of your USO M40A3MVP 360 Tactical rails that were used by MARSOC Marines used on some M40A3's back in the mid-2000's before the PGW EFR was adopted? A handful of collectors on here have asked me if I have any of those USO 360 rails available. I only have 1 extra rail, I bought it a long time ago. Since numerous people have asked me about it, it might just be fair to toss it up on Gunbroker. As of right now, that's the only loose USO 360 rail that I know of, the rest are on clone builds.
Please consider doing a small run of them for the dedicated collectors/clone builders. I bet you could easily sell 2 dozen+ of them. If they were available, you'd get a good amount of FOMO impulse purchases and collectors/clone builders buying multiple rails (1 is none, 2 is 1). These original USO 360 rails are pretty rare and this unique M40A3 variation actually has a cult following in the M40 collecting niche. Collectors/clone builders are just drawn to it, everyone seems to really like this A3 variation for some reason. Maybe it's the oddball parts or it looks really cool or it's just something different in the sea of lookalike A3's or all of those factors combined.
What I can promise you is that if USO made another batch of these M40A3MVP 360 Tactical rails, they would sell out and you'd be making a lot of people very happy!
@USO-Josh, I really hope that USO takes this into consideration, and please shoot me a message if you'd like to discuss anything. I can tell you anything you want to know about the M40 collecting community and what clone builders are looking for, whatever I can do to help USO with any information I have and you might need. This is definitely an item that's high up on some people's list, it would be awesome to see a limited edition release of these rare rails!
Here's a link to a thread I did about my MARSOC M40A3 build:
https://www.m14forum.com/threads/marsoc-m40a3-build-complete.501778/