Ok, we have an FAQ section for a reason. It's not just too look pretty sitting by the window or to suck up bandwidth. Within the FAQ there is a stickied post called, oddly enough, "Importing Airsoft and You". You can find it here:
Within this post, you would have found (had you bothered to read it) the following statement.
"Okay, so I can’t import guns. What about parts and accessories?
Yes. The good news is that most parts and accessories, including most magazines, can be successfully imported by individuals without requiring a BFL. Examples of things you CANNOT import:
- AEG magazines with fake cartridges (i.e. P90, G36, SG 552 mags)
- Frames, receivers, and metal bodies
- Suppressors and silencers
- Prohibited-length outer handgun barrels (i.e. USP Compact, Glock 26)
- Hand and 40mm grenades that look real"
Now, yes, there are people who order these items (and full guns as well) and some get through. Well, even the sun shines on a dogs ass somedays, so what? They got very lucky. If you did indeed have this item seized, you will receive a notice of seizure and you could appeal it. In this case, you'd lose and in either case, you're now red flagged and customs will open everything
you import for a very long time.