I’ve really struggled with the first of Evans’ Brimstone Angels series for a long time, too. The rest of the series was easy to come by, but the first one goes for over $100 second hand.
My local library had it for a while, but seems to have gotten rid of it. Thankfully, all Evans’ books are excellently narrated in audiobook, and are also available in ebook (including easily pirated, which I don’t feel too bad about considering I’ve bought the physical copy of all but the first, as well as the audiobooks of all of them).
I would guess the same should be true of Cunningham’s works, though I haven’t looked. (And the quality of the audio narration may not be as excellent. I know the narrator of the small number of Greenwood books I read was less than stellar.)