Hi Veiled,
That Sweedish rifle you've considered is an excellent rifle. From what I've read, it's an extremely accurate rifle- looks nice too! As far as the bullets it shoots, I don't know how easy those are to come by, or how expensive they may be.

If I had to pick an old rifle, it would be without a doubt the SKS. It is a great shooter right out of the box. It is very powerful, yet the recoil is light. It is rugged, dependable and will shoot no matter what environmental conditions it's exposed to. It is easy to disassemble and clean. Many people use them for hunting and target/recreational shooting. Large to small-framed people can shoot this gun easily. Parts and stuff are easy to find for this gun... I would pretty much leave it 'as is'- don't be tempted to put a high-capacity magizine as these tend to be problematic (if you need a gun that shoots with a high-capacity magazine, get an AK). The SKS is great the way it is designed. Not only is the gun inexpensive, its ammo is very ECONOMICAL and easy to find at most stores that sell ammo. There are also SKS forums on the web too. If you want a powerful hunting/plinker gun that you will enjoy shooting with the best bang-for-the-buck, the SKS would be the way to go. Hope this helps.