You indeed need a subscription to access the source packages. You can get by with a temporary 60 days subscription for free, but that obviously expires your access to updates after the period.

Regardless of this, a community could received these packages and updates from a Novell customer and rebuild them in an automated fashion.

However this is a difference with Red Hat that may influence the reason why there is no OpenSLES today and maybe the first act to get to an OpenSLES is ask Novell to release the SRPMs that are unencumbered.