Hi Martin
Very nice and interesting project ahead of you - but not without challenges, depending on how original/authentic you want it to
I'm not one of the hard core Burns experts round here, but I would have expected to see a Mk 9 vibrato on this. Present unit is probably a replacement (for some strange reason, as the fitted unit doesn't look to be an obvious upgrade, and not a type I've ever seen before).
Finding an original and complete Mk9 vibrato is difficult, but they do come up from time to time (often marked Gretsch on the arm though - as the Burns Mk9 design were used on Gretsch Firebirds, Silver- and Duo Jets etc). The last Mk9 I saw on ebay went for £95 about 2 weeks ago (which was probably a lucky buy, I think they often go higher), and it was an alu/chrome version and didn't include the string bar to hold down the string in a proper angle for the bridge. I have some pictures if you don't know what a Mk 9 plus the string retainer looks like.
I believe all hardware on Vibra Artiste Deluxe’s were originally gold plated, but I’m not sure. Is this the case with yours (hard to tell from the pic)?
Another question is if there's any routing done to the body to accomodate the replacement vibrato - which I would imagine given the type of the unit - the routing could be too large to be covered by the base of a Mk 9 unit, and also the colour of the body could be different under the present vibrato plate due to fading. I would check that first thing.
As for the pickup switching/wiring I don't know how it was originally - but I would guess on/off for each pickup. The original switches was probably very heavy duty and are impossible to find I would guess - but usable replacements should be available I think.
Further restoration issues are body finish, broken/missing piece of scratchplate, maybe (?) unoriginal cover on headstock etc. Would be interesting to know how and to what level you plan to restore it to it’s former glory?
Erik