Bit the bullet and ordered a pair last night - ended up being a reasonable call because today they're back up to $75. Will report back here with pictures whenever I get the time to install them. It looks to be a lot more challenging than the door speakers.Thanks for the heads up but that appears to be an American deal only. However if you DO pick some up let us know how you installed them. Would be VERY interesting to follow.
Also was randomly thinking about your speaker issue, @Digi and the more I thought about it, the most logical explanation would be loose power connections. That would explain why you need to supply so much power from the amp just to get them started. The circuit is likely still connected since you're still able to produce sound by cranking it up, albeit at a likely compromised fashion at that since you need to supply the additional power to produce it.
If that ends up being the case, and you still haven't found OEM replacement harness connectors, might be worthwhile to just splice the wires on directly using Posi-taps or something similar.