Is there an extender with external antenna that works with RBR40 router with RBW30 satellites

Maybe running an ethernet cable from the satellite in my garage to an access point in the pole barn would provide the most reliable wifi service to the pole barn.  I have an old Netgear EX6100 that can be used as a hard-wired access point.  However, running a wire will be a chore.  Drilling through the garage wall, channeling under a concrete sidewalk with a water hose hooked to some 3/4" conduit, coming up through a concrete floor in the lawn shed.  Once I get that far I have a conduit from the shed to the pole barn I can run the wire through.  It even has a 15 year old chalk line string in the conduit to pull the ethernet wire.  Hopefully it's not rotten and will take the stress of pulling the new wire through.  Years ago I enjoyed the challenge of doing something like this.  Now that I'm in my mid 70s it's more work than play, once I get on my knees .... it's hard to get back up standing.  :-(  Yeah, boo hoo, whoa is me ..... getting old sucks but it beats the alternative.  One of my favorite quotes:  "The spirit never ages, it's the body that ages, failing the spirit"  George Harrison.