The little dots or freckles on the leaves strongly suggest Elaeagnus rather than Viburnum - possibly its Elaeagnus macrophylla

That's great. I'm researching whether it's still possible to find a slow-growing one that I can grow in a pot.

Eleagnus are large shrubs. Why not try a sarcococca? They are just coming into flower now and are very strongly scented.

I have one of those already, a S. digyna which is not well sited as it hasn't really grown much since it was planted about 10 years ago.

The eleagnus's fragrance is breathtaking as you can smell it from afar!

If it's growing well, sarcococca will scent a whole garden. Where have you planted it?

(Embarrassingly) it was sited in a shaded v. sheltered end of the flower bed when I had some trees, but they got felled about 10 and 2 years ago, so now it's almost in full sun which, I know it doesn't need. The other woodsy plants I have there have fared well ie. hellebores, cyclamens etc. without issue. I guess, with the garden so over-filled with other perennials, they get a bit of cover from the sun.

The sarcococca doesn't drift over the rest of the garden. It's not put on much growth in ten years. Say it's about 10" tall and 5" wide. Some of it's branching has 'burnt'-like ends to them, so I know it isn't happy. I'll move it after flowering into the shadiest part of the garden, by my back door which only gets about 4 hrs of morning daylight in the summer .

That should suit it much better, and you will catch the scent every time you go out the back door.