Should be not a big deal to run the game and the server on the same machine. If not a virtual machine can help.
Problem with this approach should be to make it an official server, so the statistic are working. I couldn't manage to get this work last year, but I didn't spent much time on it.
Installing a DOI server can be very easy, when you have a bit knowledge about Linux: https://linuxgsm.com/lgsm/doiserver/
I touch on this in my answer to vesper_k's question, so you can look to that one for the details. You can also have a look on our roadmap here: https://trello.com/c/LiMFdYt5/1-new-units-character-diversity
Roadmap
https://trello.com/b/scOoUwpJ/day-of-infamy-roadmap
EDIT: Aparently I have mistaken DoI roadmap for insurgency one.
https://trello.com/b/Co46rhnQ/insurgency-roadmap
Here LUA is listed. For now LUA is mentioned only on DOI wiki.
The mod is a total conversion, there are all new Weapons / Uniforms / Maps / Officer Support / Classes / Voice Acting.
Day of Infamy was a mod for Insurgency, made by NWI Devs. Insurgency was a mod for HL2 originally as well.
Download and run CPU-Z (the ZIP version) and click on the Memory tab. Even if you can't/won't OC your CPU any further, I'm betting your RAM could still be optimized a lot further, especially given how much Ryzen's performance relies on it.