Offer received for rights in Ellis Co

Hello I received a letter regarding inherited mineral rights in Ellis Co. Is there anything going on there and is “as much as $7,000 per acre” even realistic? An ancillary probate would be required since I am not in Oklahoma. There are no current leases that I am aware of, all the wells my mother was getting paid on haven’t produced for at least 20 years.

Section 29, E-1/2 ,SE-1/4 SW-1/4 SE-1/4 & SE-1/4 SW-1/4 Township 23N 23W, containing 160 acres, more or less

Section 28, NW1/4, N1/2 SW1/4, SW1/4 & NW1/4, SE1/4

Township 23N 23W, containing 480 acres more or less

Thank you,