Its Your logic which is lame, Bd as a river country is just your lame excuse in the first place. If Bd move most of their goods and people by river means you hold most riverine transportation in large number, but they dont. Even your shipping industry is yet to reach million tonnes milestone.
First show me Bd armored car design till now? Or where they assembled Btr 80? No one can do because you dont have such facilities and gave no effort for such adventure. Your excuse is not working here
There is lot of case where private owned companies and state owned companies whose main business is building consumer car had main side business to build tank and armored car, Daewoo, Toyota, Hyundai, Kawasaki, tatra from Cheko, and there is case where private companies such as Renault provide their best engineering skill to help project like VAB, VBCL and among other. Have strong car company and manufacturer working in your country surely will help alot.