Get it at Zavvi on Blu-Ray (1 Disc) for £12.99 with Free Del, and save £7 off the RRP.
This movie has not long been released on Blu Ray & DVD and is not yet widely available. It has been digitaly remastered and might just make a nice xmas pressie for someone.
* Please note Zavvi have made a mistake with their product description as they have the Episode list for an old Super Mario Bros cartoon series, but the item is definetly the Motion Picture Movie.
For comparison the only other availability I am aware of is Ebay £15.99, and Amazon £19.99. The Blu-Ray is even cheaper than the DVD!
Possible codes you may be able to use if your lucky and worth a try:
10% off for new customers using discount code @ Zavvi
courtesy of dbrazuk
£10 off £100 Spend using discount code @ Zavvi
courtesy of andywedge
PS 1st post for me, so spare me a bashing just this once :)