A new composer just viewed the 22 minute production and said the visual effects look very professional and wants to up the price. Are they really that good? Or, is that just to up their rate?
Thank the composer for his time and interest. Then run the hell away from them. That's just sleazy. As Nick said, people have been taking you for a bit of a ride.
Composers are often flexable with rates, to fit the budget/requirements of the project. But they never EVER go up because the project looks professional. They go up if you want more on a shorter timetable. They go up if you insist on having a first chair symphonic cellist play the music. They go up if the composer needs to book studio time, hire other musicians or if they just don't really want to do the project. Never because it "looks professional."
Saying this with all humility, unless the composer's name is Danny Elfman or Howard Shore (etc, etc), no one is going to care. Your peers might. Your audience? Hell, half the time they don't even NOTICE the music. A network you are selling the pilot to? Not a bit. If they pick up your project, you'll have the money to hire whatever composer you want/they want you to. So for the pilot, you need someone who can do a good job. Lots of people can, established or not.
So here's my unsolicited 2 cents. When you've finished (if you haven't already) the final edit, post a "composer wanted" here. There are a lot of us around, and lots of folks who are good, but don't have a lot of experience. You can find someone who will want to do it for free...maybe not 100% as good as you want, but there are some really really good people around. Make your pitch. If you get picked up, give the composer some cash. Then either keep them, or look for someone new within the budget you have.
Of course, selfishly I think composers should be paid well all the time. And given cookies and adult beverages. But this person is trying to take advantage of you, and that's just crap. We're all in this together.