First of all, if you wanna conduct an MO, you'll have to do the legwork -go look for a dealer who can give you good prices if you order X sets, freebies etc. Then just post it in the Consumers forum, stating the price, how many units must be booked and the last day for booking, as well as payment terms.
Alternatively, there are several people here who organizes MO's on a regular basis, you can just PM them directly to liase with them. Good luck!
I doubt you'll be able to get a very much lower price for the D70, you should just go to a shop like Lords and ask them the best price they can give you if both you and your friend were to buy.