Written by Angus Grant, fiddler for the Scottish celto-punk band Shooglenifty. Don’t take the key signature that seriously. The tune is in an Eastern mode of some sort or another, reminiscent of "Kandahar" https://thesession.org/tunes/3310 which I submitted a while back.
They play it both very slow and rather fast. Listen to the recording before making your preference.
Here is how I play it:
T: Arms Dealer’s Daughter, The
B2AG EedB|edBe dBAB|B2AG EBAG|DEED EGAB|
B2AG EedB|edBe dBAB|cBAd2 BAB|GABA B2 B2:|
e2dB gedg|edbg agef|e2dB ged(A|A)BcA B2 B2|
e2dB gedg|edbg agef|gfea gedB|ABcd e2 e2:|