Where can I get?

It doesn't have to be re-routed.
What you want is what they call an 'S' trap pan.
Go to B&Q, Wickes. Focus,Homebase see what they have that has the outlet pointing down [S trap] not what you've seen pointing horizontal out the back of the pan ['P' trap]. If you can't see an 'S' trap one ask at service desk if they can get one. Failing that look up your nearest bathroom/plumbing shop they will get one if they haven't one in stock.

Take a look at www.bathroomtrade.com
Click on the 'Contract Sanitaryware' picture
on the page that appears the pan you want is the one on the right second one down , low level 'S' trap
who's replacing it? if you want instructions email robertwhiting76@hotmail.com. I've had my fill of replacing toilets now retired.

Bob
September 2008