Honestly? I'm really not sure.
I think it's a genuinely lovely idea to want to help relieve the pain but scissors are such a personal tool. Are you certain that this is the best type of scissor for your wife?
For instance, there's the type and length of blade to consider, the weight/balance ratio and whether to use an offset or straight handle.
All these options are very personal to each hairdresser and using the wrong type of scissor could actually cause more problems than it solves. I have 4 pairs (excluding texturising scissors) and two of them are used more frequently, depending on what I'm doing.
I must admit, I think that $400 is reasonable for a decent quality pair. Many colleagues pay upwards of $600.
If I was looking to buy a new pair, I'd probably want to visit the beauty wholesaler directly and pick several pairs up and see how they feel in my hands before making a final decision.
Sorry, I don't think I've really helped you.