Ehobby have always under-declared the value of my items even though I never ask them to, so I never had to pay customs fees unlike with ASGI or Evike.
And like RECKLESS said, you probably had to get service from UPS due to the nades. But if you take a Guarder Infinite Torque-Up Motor for example, it is $75 on airsoftparts before shipping and taxes. On Ehobby, its only $36. If you dont mind taking the slow shipping, its probably less than $50($42 for me) in total.
Lastly, do you have an account at Ehobbyasia? You know they give you 5% off your total order for just being a member right? I don't see that discount on your calculations.