Enligt Memory Alpha har det varit en del debatt över det. Men det verkar vara ja, det är i Delta-kvadranten.
While the Sikarians explained that they could reach all planets in their quadrant, it was not explicitly said, and nor does it follow, that Alastria too was in the Delta Quadrant. However, according to Startrek.com and the Star Trek Encyclopedia (3rd ed., p. 5), this planet was located in this quadrant.
Detta från Startrek.com :
A Delta Quadrant planet with a binary star about 40,000 light-years from Sikaris, accessed via the spatial trajector.
Så förutsatt att Star Trek Encyclopedia är den mest exakta informationskällan, då kan du säga ja det är:)