Take this with some caution, but according to the SRW Wiki, the show Southern Cross will never be in an SRW because ever since 2005 Big West and Tatsunoko have been fighting over it and now the rights to it are all over the place.
That might explain the lack of merchandise on both sides of the pond. Without a visible Japanese foothold, how can they expect to do anything other than a few crummy T-shirts.