While I appreciate having the "Real Deal" would be Awesome, there are other factors that one must take into consideration.
Noclass_Nick lives in New Zealand ( as do I ) and I can say that arcade parts are
not in ready supply like many other countries.
The few vendors that sell arcade parts in NZ demand such high prices that its just not cost effective to use them. Importing stuff like a screen is out of the question.
I made my cabinet with a 32" LG LCD Tv and can say without a doubt that mame and the use of a graphic filter More than makes up for the lack of a real arcade monitor.
I say run with what ever you can afford and do the best possible job you can. 99% of people who don't have an interest in authentic arcade gaming wont even know the difference
Its the fun with friends and memories that make experience

What ever you decide on, Please Please Please scale the cabinet accordingly. There is nothing worst that a awesomely made cabinet with a screen that's simply too small.