Here is a great comparison between different noninvasive brain stimulation techniques for depression: https://www.bmj.com/content/364/bmj.l1079
There are also a few antipsychotic-like drugs that are used at low doses for antidepressant effects along with other antidepressants, but I'm not sure if the newer ones are indicated for depression, or if the newer ones are just reformulations of existing medications. It looks like there's a newer olanzapine combination on the market.
Unfortunately for SAINT it looks like you also need fMRI to correctly target the therapy...that's going to be a bit tougher to DIY.
You can also search this TMS FB group https://www.facebook.com/groups/285541688306686 for "saint" and find other people's experiences.
Edit: Apparently, the clinics that claim to be offering it might just be doing something that is loosely based on what is publicly known about the SAINT protocol. Dr. Nolan Williams hasn't released full details, so it's not possible for clinics to replicate it exactly. This clinic https://www.cambridgebiotherapies.com/accelerated-tms/ talks about how they've tried to reverse engineer the protocol at the bottom.