yes there are several statements showing the reach of the trader empire: such as the eastern reaches, the western front(tec/vasari war), the core worlds( the original systems that the settlers colonized), and the northern kingdoms. now we know that the vasari have conquered at least if not more than half of the western front. the advent have taken the eastern reaches. the core worlds consists of multiple systems, the northern kingdoms are rich trader worlds, the western front is perhaps the smallest of the trader systems, now the eastern reaches is the trade orders industrial juggernaught, now there are a few small systems that dot the map around these stellar giants, they consist of small single to 5 at the max planet systems.
all facts in this reply are drawn from multiple sources on the sins web site.
some facts may not be entirely accurate.
AncientEmperor.