I don't know varieties off the top of my head but look for typical gardening books by the likes of Percy Thrower. My dad had one of his in the 70's that I remember reading a lot.

I had a book by Peter Seabrook, published in the seventies I think, that was all about conifer and heather gardening - the two went together in the seventies. Unfortunately, I gave it to the charity shop some months back, since I'm never likely to plant anything like it - I've checked and I can't find it available anywhere. MIght be worth checking the library or charity shops - even a copy of the Tree and Shrub expert (one was published in 1983) included lists of conifers.

I do recall most of the pictures included layouts with very large and less large rocks amongst the mix of conifers and heathers - there was also a large range of conifers included, so really, almost any conifer that was available in the seventies, and of the right size and shape for the setting, will have been used. That means you should probably exclude any new varieties which have been bred in recent years. I remember the following though: Juniper virginiana 'Skyrocket', J. communis 'Compressa', Cupressus macrocarpa 'Goldcrest', Juniper media 'Old Gold', J. Meida 'Pfitzerana', Chamaecyparis pisifera 'Boulevard', Chamaecyparis 'Minima Glauca', C. lawsoniana 'Columnaris', C. lawsoniana 'minima aurea', C. Ellwood's Gold, Picea glauca albertiana 'Conica', P. abies 'Nidiformis'

Perhaps the GoY member 'Bluespruce' would be able to offer some guidance? Not seen him around for a while, but he's definitely a Conifer expert.

We had a chamaecyparis nana Gracilis around that time