Not sure how things specifically work in Canada, but there are some similarities with US law due to it all deriving from British common law (except for Louisiana, which bases everything on the Napoleonic code).
For one, the court considers not the value to buy new, but only the value to replace. This helps and harms depending on circumstances. Say you buy a new xbox game for $60 and I smash it. The court would only award you the average second-hand market value of maybe $40. Ah, but what if the item in question is a collector's item that's no longer in production? Doesn't matter how much you bought it for, it only matters how much it costs now to replace it. You can see how this is advantageous.
Like a classic car, the dollar amount in the suit will probably revolve around how much it costs to repair. Here in the states, reproduction parts are usually used as opposed to (much more expensive) OEM parts unless you can convince the judge otherwise. However, there isn't exactly a huge after-market for pinball parts compared to car parts. Especially when it comes to plastics and toys and artwork pieces that cannot be reproduced by multiple sellers without copyright infringement. This also works to your favor, because the shippers can't fall back on cheapo inferior copy-cat parts.
Here's what you should do if you haven't done it already. Take an inventory of every individual part that is broken or not working properly. For each one, look up how much it would cost to replace it from at minimum three reputable sellers (pinball life, pinbits, marco, bay area amusements, etc). You might not even be able to find more than one seller for some parts, in which case you might have no choice but to look at ended ebay sales. Get quotes from at least 3 reputable restorers on how much it would cost to do the repair (including building a new cabinet and adding decals).
My point here is that the shippers are going to take you to the mat claiming that you're just spouting off whatever inflated prices you can think of. The judge won't know anything about pinball or the pinball market, and they will take advantage of that. Your goal is to get all that pricing info to your lawyer so that he/she can make the judge see reality.