Ue, it's not in the best condition, but you may be interested in this:http://www.ebay.com/itm/360306775272
If so, better be quick as it has a couple of watchers and a few offers been made.
Note that it won't quite fit a standard size Aus plate, but depending what state you're in, you can get standard US-sized plates, NSW (where I am) being one of them. Otherwise just a cool bit of relevant period memorabilia for your shed/workshop wall.
EDIT: did some searching. Found a thread regarding a car that was sold new from that dealership, link HERE
. Couple of the photos show 2 different addresses, which look (as best I can tell) like:
Corner S Riverside & Barnett, Medford OR
227 E 9th PO Box Medford OR
Can't find anything current under that dealer name, although there is still a dealer on S Riverside - Dollar Buick GMC.
Also note that on the 1980 paperwork via the link above, the dealer code is 19-108, which is different from the 19-107 on your NCRS Report; seems the dealer codes could change over the years, so would imagine sometime between when your car sold and 1980 it was changed from 107 to 108.