Ebay and other sites sell coupons such as TheCouponClippers.Com. Also I have discovered a treasure trove of discarded newspapers with inserts but don't explain me to reveal that source or folks will be all over it like flies the next time I harvest those coupons.
We used to use couponclippers but lately have found better deals at mycouponhunter.com or collectablecoupons.com
IIRC mycouponhunter does not have a minimum order requirement.
Rite Aid has Blink Eye drops 7.99 with 7.99 rebate. Have to wait for the rebate but it’s free.