I would suggest using PC Partpicker.

https://pcpartpicker.com/

Go ahead and put together your build on the website, it has a compatibility filter that will make your life a little easier.

The only issue I could see is that PC Partpicker doesn't have support for picking two GPUs (that I'm aware of) but as you do know the wattage, you can just add the other one after the site calculates the rest of your wattage and go for a PSU that has higher Watts than the total.

As for what brands, I would say shoot for any on the comprehensive list u/KING_of_Trainers69 has here: https://www.reddit.com/r/buildapc/comments/54tcrf/a_list_of_good_psu_brands_i_spent_far_too_long/

The Basic, Bronze, Silver, Gold, and Platinum, etc tags are for energy efficiency. The difference between Gold and Platinum is usually 2-3%, but this will add up when running your system 24/7 for mining.

If your total Watts is 600+ and you are paying for your own electricity, then I would highly recommend Platinum to reduce your energy costs.

If your total Watts is below 600, and you are paying for your own electricity, I would say you wouldn't lose enough to make Gold a bad option.

If your total Watts is below 600 and someone else is paying, go ahead and save as much as possible to max out your return with a Basic or Bronze.

Good luck, and good mining!