Your spur looks very much like a US model 1859 spur. However you have a very unique bend to the portion that holds the rowel, and I can't find an example of that exact spur. I don't have a copy of Crouch's book, but I was using the spur book by Bob Baird, PhD.
Could be civilian or a union spur, but for sure an 1800's type . Congrats on a finding pretty much a complete one . Most of the time you end up with only half of one or a piece of it. Congrats on a nice piece of early history.
You have an 1859 Civil War Calvary Spur, so congratulations!
Yep, it is bent a tad but that's okay. I have found a number of these that are bent, it's not uncommon. So, there were a ton of private contractors that serviced Uncle Sam so there may be variances on some of the different styles.