You should be able to sharpen it with a new file. You want a tapered saw (triangular) file that will stick out over the teeth about 1/2 the width of each side. The tooth per inch will determine the size of the file. The fact that the starter teeth are cross-cut and the rest are rip are no problem for hand sharpening as you sharpen each tooth individually. A machine shop sharpening may charge extra because there are two set-ups. It is a good profile for a rip saw as the cross-cut starter teeth make it easier to get it going.
However, if you have no experience, you may want to enlist the help of someone who knows how to sharpen saws and has the right type vise or jig, and is comfortable with both tooth profiles. If it is really worn, it will also need jointing (getting all the teeth the same height and flat with each other so the edge is straight) before the teeth are sharpened. There are a lot of web references and books on the how-to for the basics.
It is not a hard skill to learn, but does take patience and a bit of practice. The results are phenomenal, tho, and if you learn them, you will never use a "store-bought" one again without first tuning it up yourself. Even the "shark's tooth" saws can be hand sharpened, but you have to add in another angle (upward) that complicates things.
Sandvik is a good quality, and the age says that the teeth are probably not induction hardened (which also makes them brittle when setting the kerf), which I would suspect means it has been made to be resharpened. Its probably better quality than you can buy today, so I would think its a keeper._
JMTCW
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