Even given the salary scale it doesn't quite tell the whole story financially without knowing what would be sacrificed in lieu of other expenses (food? utilities? weekend keg parties?)
It all depends on how much that keyboard factors into your daily quality of life. I am a terrible financial advisor, and quite broke more often than not, BUT I find that some of the best things I have appreciated are items of high quality that I maybe spent more on, and also found that they tend to last longer as well, prehaps because I care for them well. Only you can decide how much something is worth to you, and if you feel you want it badly enough that you won't suffer from having spent the money on it after the fact, then don't let anyone else tell you you shouldn't based on the numerical price tag alone. Value/=Price. Value is better measured by comparing the non-money costs of how your life will be improved by having it vs how your life will be unimproved by not having the funds allotted. It also bears consideration whether it can be considered as an investment in a future return if you intend to make a living with your hands on a keyboard every day.
Who was it that posted here that they had more often regretted spending less money on a lesser quality thing than regretted buying something pricey but higher quality? I had actually wanted to put that on my favorite quotes to remind myself of this when necessary.
Especially when I am not having money, it is hard for me to remember that it is a TOOL- and the desire to cling to it for its own sake is the epitome of foolishness.