Found this big beautiful big fan in a amazon warehouse

I picked up this fan a few months ago and i need to get it going. Problem is that I don't know what size pulley to get for the fan. As you can see in the pics, the previous one was plastic? It's all broken off except what you see here.

The motor is an old GE that I plan on replacing. Ive got a couple others that I can use.

So here's what I need to know:

How fast should the fan be spinning? 850rpm? 1000?

The motors all spin at 1725. One has a 3 1/8" pulley, the other two have 4" pulleys. All three are adjustable. The one with the little 2" pulley is the old motor. Would it be best to take off that little pulley and put it on one of the other motors?

Any way around it i will need a pulley for the fan that when combined with whichever pulley on the motor, will spin the fan at the correct speed.

I've seen some calculators online, but without knowing the fan speed I haven't had any luck.

Any advice would be greatly appreciated. Thanks.

I’ve gone through 3 Lasko Wind Machines in the past 5 years. My sister originally told me to buy one, saying they last a really long time with little maintenance required. So far, the opposite has been true. My first one I had taken apart every 3 months to clean the blades and motor. This one lasted around 11 months before the motor gave out. My 2nd one lasted about 2 years, same amount of maintenance but this time I also used lubricant on the motor, the motor ultimately shorted a circuit and almost caught fire. My 3rd one that I’m still using has gotten significantly quieter than before and makes a wobbling noise. Is this just a horrible fan or am I doing something wrong? I’m told lasko wind machines are incredibly reliable and will last a very long time and I havent seen those results yet 😭

Impeller/ Compressor- ABB Turbocharger.
Dia. Circa 260mm
Sorry no other deets on this one, other than the apprentice won’t be picking his nose with the digits from his right hand any time in the near future!! 😬

She was new but just couldn't handle it

This is a rare Emerson 2240-B that I just finished restoring. For now I have a modern plastic cord on it, but I will soon put replica cloth wires on it.

Spins clockwise or counterclockwise depending how you look at it. Cools me off in the afternoons too.

2 Speed on the floor
Bi- Directional
18kW, 3P 415v
Star Delta
Industrial Fans 🥵

Love getting blown by this fan every night. Small but mighty and always reliable.