I have 2 Russian Mosin Nagants. One I am keeping stock with the iron sites. The other I purchased a promag arch angel sniper stock for it. I want to add optics to it. I bought a brass stacker see thru scope mount with picatinny rail that sits over the rear iron site. I am looking for suggestions as to what would be a good long eye relief or scout scope to use without breaking the bank. It's an inexpensive gun so I don't want to go nuts with the optics. It's mainly for target shooting on a 300 yd range. Thanks for any suggestions.