Perhaps the nearest thing to an Inokatsu build are those airsoft rifles made by Vipertech from Taiwan. In this video, Nextgen Retros goes over their Colt M16/M16A1 Vietnam Model 603 Gas Blowback Rifle... "One of the best M16 GBBs on the market. Forged body and a lot of steel parts. I need for the future an A2 Upper Assembly too!"

Check this customised Tokyo Marui M4 SOPMOD NGRS that was turned into an M16A1 XM16 NGRS by Nextgen Retros. This uses a custom E&C Upper, custom G&P AEG front set, and a custom AEG stock. The next plan is the installing an A1 correct as well as a period corect A1 G&P stock.

We hope that the Tokyo Marui product designers are watching this and may want to design retro NGRS airsoft rifles such as the XM16, M733, and more.