I need a fan blade arm is broken I have ups 7-59590-29006-2 model 5745
120v 60hz
e127609wh10307 the fan is 11 years old I just need the part that holds up the
Blade into the motor

IF you could find the part, you still have an 11 year old fan. HD and Lowe's have some blade brackets. However, the weights must match so you might be better off getting a new fan.

Another point is that newer fans are more energy efficient, too. Even when you put in a new fan it is a good idea to check the tightness of blades regularly and to use a little Locktite thread compound on the screws when you assemble a new fan. You may find a set of brackets, but like the above post pointed out, all will have to be replaced so that they match weights. If you have a good set of scales you can check the weights of all the brackets with blades before assembly, too.