The 77x57 Model 77 RSI Mark I (tang safety) is a hard to find, very desirable , hunting rifle/collectible. In the 200th year model, NIB, you are looking at a steal at that price. I have seen rare examples of the non-200th year with price tags @ $1000.
Go for it. But stick it back under bed. As soon as you popo a few rounds or even mount the rings, the $ value falls off steeply. Get any paper work with it, including original bil of sale.
Or at that price slip a a 4x Leupold her and use it for what Bill Ruger intended
Hard choice.
Good luck,
oneb