Seconding that PSU repair isn't really worth it in my opinion - unlike something like a monitor, new arcade PSUs are generally better made and that if you don't require any specific connectors or dimensions, you can find one that'll work well pretty cheaply.
That being said, if you've never recapped anything and would like to try, then go for it. If you have the right tools, it doesn't take that long and is a good skill to have