You can get a brand new mpc500 pritty cheap here in the uk if you know were to look.
i payed
£200 for mine, thats (226euros / 322dollars)
the uk is a wierd place and street prices dither vastly depending on were you are in the uk
there some (a lot of) very upper class parts of this country were you can expect to pay 10 times more then you would in our very very very low class areas (which are basicly what americans would call ghettos, the uk goverment would rather people dont know about these places).
belive it or not the really really f'd up parts of the uk are pritty dangerous and outsiders wondering around these areas will more then lighty get robbed at the least but killings are not uncommon.
if your willing to risk it or are unfortinet enouf to live in one of these areas, you can get pritty much anything for a fraction of the price you would pay in a 'normal' part of the uk

infact i know a shop in croyden, south london, were they have an mpc2000xl in perfect working order for £150 (cosmeticly the shell was a little scratched but still it worked just fine), several new mpc500s for £200 an mpc3000 for £450 2 asr10s both goin for £180 the lists goes on and on they even sell brand new mac book pros in the store nest door for £300 less then the highstreet stores only problem is you gotta walk fru one mad bit of croyden to get there n down more then a few alleys.
n odds on you'lll probly bump into these lot
http://www.youtube.com/watch?v=IjGQhv6U ... re=related (i know there musics utter krap an if they stole ur music production gear then wudnt know wat to do with it but belive me they would steal it given half the chance)