What's the width of them, if they are the same and same material (e.g Alu) then they would be fine. If you're replacing plastic spacers then they used to ba a touch wider than the equivalent Alu/Steel ones for which I can only say was due to compression on them.
Talking Way back when though in 7 speed era.
So err check the width, but any spacer that isn't to heigh for the smaller sprockets should be fine.
Oh and on shimano the colour changed to signify it's width (again may have changed that stance with modern setups .)
EDIT might sound daft, but they make a PG970 DH version that has all the red parts you need ? http://www.chainreactioncycles.com/Mode ... elID=57562
See if ebay has a knackered on and use the spacers. Might be cheaper as Alu spacers don't seem to be cheap on their own.