Free channels:
Sky One
Sky News
Sky Sports (soft encrypted, requires decoder but no viewing card)

£9.99 per month (2019 adjustment: £19):
One of the following Premium channels:
Option 1: Sky Movies Plus
Option 2: The Movie Channel

£14.99 per month (2019 adjustment: £28):
Two Premium Channels:
Sky Movies Plus
The Movie Channel

These channels were available via both Sky Television’s PAL service via Astra transponders and British Satellite Broadcasting’s D-MAC service via Marcopolo transponders until their eventual shutdown on 31st of December 1992.

With the introduction of premium subscription channels, initially only movie channels, came the need for viewing cards. The earliest viewing cards, as applicable to this subscription lineup, were as shown at the top of this page. For more information, see this page.

Source: BSkyB dealer channel broadcast on Astra 19E. (early 1991) (YouTube)