If you are going to run 40' of LMR, it would need to be LMR-400 at least to minimize loss. As such, you will likely want to use RP-SMA to N jumpers regardless for strain relief on the connector. As such, you could use the ANT-2x2-2005 or ANT-2x2-5005 antennas, which do have N connectors, to replace your ANT-19s.
Note that indoor APs with connectors are designed to be co-located with their antennas (ala within an enclosure or oberon box), and in those cases there is no need for ruggedized antenna connectors where longer LMR runs would be used.