Mini is the fast marker etc but have proven unrelibable at times... the eos is a good marker but not really fast enough for tourament paintball.. have a look at the PMR a very good gun for the money...
Pump wise, i have some second hand traccer pumps, very good vert reliable and easy to fix... £20 to your door
There's a massive range of secondhand markers for £250.
You wanna be looking at Ego's,Dm's,Pm's,Angels,Timmy's,Shockers,etc,basically the higher end of the market.