I would very much doubt you can use mil stuff. From memory, even the part numbers are different.
From memory (I sold my AB 10 years ago when the problem became apparent re fitting Bell parts to Agusta Bell machines), there was a process whereby if you bought a new Bell part, shipped it to Agusta, they would then inspect it and issue the appropriate EASA Form 1 to allow you to use it. I can only imagine that this comes at a cost....but it might be your only alternative.