where do you source your magazines from out of interest? Are they epubs etc?

There are a bunch of apps that do this, here is one of the popular ones https://remini.ai/.

For more DIY you could use a comfyui or automatic1111 google collab or if you wanna go cheaper use a service like vast.ai and then search on youtube “face swap comfyui” or “face swap automatic1111” for a bunch of tutorials