Hi Pete - I hope you have received the links I emailed -
http://www.cyberbeach.net/~dbardell/bellows.html and
http://www.instructables.com/id/bell...format-camera/ for any others who are interested. You used to be able to buy a black paint for bellows which you can still get - here is a link to some ideas
http://photo.net/bboard/q-and-a-fetch-msg?msg_id=003dHm
The main problem you will face is getting an enlarger that will take a 5" x 4" negative - assuming you want to do more than contact prints - Your best bet is the type of camera shop where some old gent has one tucked away in the back gathering dust - like I did until 4 years ago - mine was passed to a local photographic club - and that could be a source for you.