adolf said..
Get an invoice for $900. if You can split the item into parts then you could pay $900 for each part.
If you have two separate packages from the same place, then officially they can add the two and charge you duty if the total reaches the $1000 threshold. Whether this would actually happen in practice is another thing.
Some of the overseas vendors are real shonky. One of the websites I use actually asks you what $ value you want stated on the customs declaration. (And if you don't fill it in, it defaults to 30% of the order value!)