You can check here or when you find out what other parts you need besides the bolt, you can find them here at NUMRICH/Gun Parts Corp:
Firearm Parts & Accessories | Military Surplus | Numrich Gun Parts
You need at the very least the bolt, and there is a possibility other smaller parts are missing. If you live in England the chances of you obtaining the parts you need are not good. For a start you would need at least a section 5 licence to obtain the missing bits - unless someone would supply them to you deactivated. Whatever part of the world you live in it would probably work out cheaper to purchase a complete gun. Either that or keep what you have and be happy with it for what it is.
Books published to date... 'Belfast Diaries: A Gunner In Northern Ireland'... 'A Tough Nut To Crack - Andersonstown'... 'An Accrington Pal: The Diaries of Pte Jack Smallshaw, September 1914 To March 1919'.