[6.1] Std cost vs Lst cost

Our company is wanting to use standard costing for our standard tools
and last costing for the specials or customer orders for job costing and
quoting, and the same materials may be used/issued for both types of
jobs so I can't zero out the inventory and change costing method by part
number and reenter qtys unless I do this just before issuing and then
change back but that is not really practical and I'm not sure how the
system would show previous jobs/issues etc. Is there another way I can
get this set up or maybe a special report by job type of last actual
purchasing price?
I appreciate any responses on this as I'm not sure how to make this happen.
thanks
dennis