A lot of Armenian priests, including my own, will give communion to EO's, stating that there is no difference between us. I know of at least one Greek church in my area which gives communion to Armenians, so there is some reciprocity in this.
However, there is some controversy about this and I recently heard a deacon from another Armenian church speak out and condemn the practice, since we are not formally in communion and the EO's still consider some of our saints to be heretics, etc.
If you do not trust your priest's opinion on this, ask your bishop. If your bishop tells you it's O.K. and you still don't feel right about it, then maybe you still shouldn't take Communion in the Armenian Church. It is not worth it if it is going to cause some lingering doubts in the back of your mind. The doubts may eventually turn to regret and that is not a good thing.
I personally don't take communion in EO churches, even though my priest (and probably my bishop) wouldn't have a problem with it. Even though I believe we are of the same faith, I still think we need to go through some formal process of union before we should be taking communion in each other's churches.
That's just my 2 cents.