Thanks. It has the number N700588 near the saddle, but I can't find information based on it. I tried this "Cykelhistoriskt register" which had many serial numbers, but not this one. Also none of the images in the site's picture section matched.

I would also prefer to keep is as original as possible, maybe I should just get someone to change the spokes from the wheels, and perhaps the hubs, at least on the front wheel it's a bit shakey and I'm not sure opening, cleaning and oiling it would help.

I'm no expert either when it comes things more complicated than changing tires and your basic adjustments, seems there are so many similar spare parts out there and I always get the wrong ones which leads to frustration.