[EC900]

Nickelplated: Go to the dmv.ca website. There are plenty of options for online transactions, it will explain what info you can obtain. As stated, this should be no problem since you are the owner of record. I don’t exactly recall but they purge files from digital records after a few years of ninrenewals, but I think they will do a hand search for your old title/reg for a fee, it requires you supply your info to verify your identity to that of the info they have on file. You can also call them, but be sure you get someone with experience in Titling Dept and not a general customer service call taker.

As for re-registering in OR, yes, your local dmv can and should do this based on the old docs you have. Simply a transfer, pay fees get new title.
But, you have a gem and for the sake of keeping copies of old registration and an original title, it always a good thing to preserve this provenance for future stewards - including the original plates and Reg cards.

Driving around w/o proper reg might be ok as any old cars attract attention, traffic enforcement would likely be more interested in the car than a citation. The only problem is to never disclose the fact the plates are invalid to insurance companies unless you’re certain they allow “unregistered” vehicles to be driven on public roads ….like only to car shows or mechanics shop.