You have the tank and stand so that's taken care of.
Some sort of filtration, your existing canisters will work, you can upgrade later if you decide you want something different.
Heater x2 I'd get 100 or 150W. Two because if one fails off or on it will give you more time to notice.
A couple power heads, I'd put one on each end, maybe one on the middle of the back wall. You can spend $50 up to $500+ on these. You don't need anything fancy to be successful. I have 4 800 gal per hr power heads I got on Amazon for $10 each 3 years ago. Still work great.
A reverse osmosis deionized water system, mine is from bulk reef supply, I've heard you can get refurbished systems from spectrapure for a very good price. Good pure water is very important.
A refractometer. Not a hydrometer.
Lights meant for a saltwater tank, for fish only don't need to be fancy.
Rock. I used pukani dry rock from bulk reef supply, it is around $3.50 per pound, free shipping. You'll probably need 75-100 lb. dry rock weighs a lot less than live rock. One or two pieces of nice live rock to seed the tank. The dry rock will become live over a couple months.
Argonite sand, you can get live or not either works. I would not get the super fine sand it tends to blow around. No silica sand and no crushed coral gravel.
You will need test kits for ammonia, nitrite, and nitrate this is very important for monitoring the cycle.
I also recomend a 10 gallon tank, sponge filter with an air pump and air stone and a small heater to use as a quarantine tank for new fish.
Salt mix. For fish only a box of instant ocean that makes 200 gall would be a good place to start.
You will need a container to mix salt water. Needs to be food grade plastic. Only to be used for the tank. You can get rubbermade brute trash cans at any big box store. They also sell things with wheels to put them on. Will make life way easier to have wheels. A 28 gallon is a good size.
A pump to put in the mixing container. You can use this mix the water and then pump it into the tank when ready.
Some people have 2 containers, one for RODI Water storage and one for salt water.
I'm sure I missed some things.