I have some spare Corgi figures too that will be available soon.
I have a genuine original blue 305 mini-Marcos GT850, probably the rarest of the normally issued Corgis from this era. This could be found only in some of teh Gift set 20 Transporter Sets issued in 1972.
A Complete Corgi Catalogue
I am working on publishing a complete listing of Corgi models from 1956 to the 1970s. This will include all the visible variations that I am aware of and which could have been purchased at your local store or ordered from Corgi, as well as a few promotional issues. It will have photos of actual models I have seen wherever possible and some dates of availability. Other than for a few items I am not proposing to cover the different box styles at this stage.
I will also not attempt to estimate values either as these can vary so much with condition. My own stock can always serve as a guide in this respect and I am happy to value individual items or collections if required.