Need some quick help

Can someone tell me the approximate value of a 25 year old Ruger #1 243 in great shape, less then a box of shells shot through. Buddy of mine wants to sell it today at a gun show and doesn't know the value of it. This guy is 88 year old WWII Vet and he has his mind made up to sell it now.

i bought a new one 2 years ago for 750.00 so my estimate is 600.00

you probaly already know this but take the scope off as you get nothing for it and he will get more for his gun if he is willing to trade for something else