Try Steve Jones at Trent firearms - he has a rather useful box of "bits" and he should not be too far from you.
I have the same problem as well, never found one ended up buying a s/h set of bases, you need to make sure weather the replacement part is cut for tapered or straight cut bases as well
Thanks, to a very kind gentleman, I think I have found the block dovetail, should be in the post tomorrow.
Thank you all for the help
Mounts that can break like that wouldn't cut it for DG or even PG rifles. When you replace them, look at EAW's offering..not cheap, but good steel