Welcome to the forum. I have no idea what boat will give you 7' headroom. However, if you buy a boat that you like that is close to 6'1'' or 6'4". You can modify it with a pilothouse or higher deck cabin
. The glass work is not hard but you do want a professional marine
shipwright to do it. It would be a shame to hold off on your dreams if you can get a boat for $ 5000.00 less then you want to pay and put the $ 5000.00 into a new cabin
I wouldn't think it would cost you much more then that unless you are looking at $ 100,000.00 boats.
Here is a link to a pilothouse 30 footer,