Hi Bill, those look like sliding backs so you slide the screen over and insert the dark-slide.

It'll depend what's wrong with the lens, is the balsams damaged then it need disassembly, cleaning, re-cementing etc an expensive business. Although some have done it themselves The lens is quite desirable to many.

Looks like a Packard type shutters fitted behind the lens, there were UK shutters which pre-date Packard's.

Better to make a new back so as to keep the camera intact. You don't give the dimensions but it'ssprobably Whole plate so a 7x5 back might be a good idea.