Amazon has these for $24.16. I use them on almost all my guns, very solid, lightweight, and precise.(UTG ACCU-SYNC30mm Integral Picatinny Rings). I recommend the 50mm offset, NOT the 34mm offset.
https://smile.amazon.com/dp/B0793FBYLJ/ref=cm_sw_r_tw_dp_U_x_8-FSDb1950WZ8
https://smile.amazon.com/dp/B0793FBYLJ/ref=cm_sw_r_tw_dp_U_x_8-FSDb1950WZ8