Just took the block to bits.
The Nos match 374. Loading / cocking Lever 374, Sear 4, Trigger block 374.
The only one that does not is the pin / spring carrier, it has 838A on it.
Just seen on the back of the dropping block the 838A again it also has 374 on the side.
There are 2 stamps on the dropping block that I will try and take pics.
Looks like the stamps ether side on the dropping block are the same.
I remember that I did not change the pin now, it was the flat trigger spring.