Props are low volume specialty products for professionals. Airsoft guns are high volume toys for the mass market.

A theater or film production company can afford expensive quality props, because they are an organization with an orginizarion sized budget. Airsoft guns have to be cost cut and mass produced to a low price point because they sell to normal people with human scale budgets.

Also the brown furniture on the NCR service rifle is wood. Be authentic, learn carpentry.