Johnny L.... I have a Gould and Goodrich 803 229 that, surprising to me, fits the Security 9 like a glove. I believe it's for a sig p229 but I found this holster worked well for a S&W 908 and 909.
I have read, and perhaps others can confirm, the Sec 9 fits very well in holsters made for the Glock 19. Makes sense since the siz and dimensions are very close.
The Mitch Rosens are very nice holsters. But I think there are many options.
Good luck....Danno