Originally Posted by Mechmaster
Options:
Old school flat 10mm plates
3mm or 5mm shims and longer screws
Salomon PE2 or PE Sport plates. Note that if you have the 997E there is no hole for the fifth screw.
DR9 plates and new screws
Poweraxe race plate (the black ones on the older 2V and 3V)
Hengl plate
Viste plates
Make your own out of cutting board material
Flat mount
Although the hole pattern hasn't changed, the shape of the base plates have changed since the 997. Thus, 900s plates and Axe+ plates cannot be back-fitted. The 900s plates in particular have an interesting ramped shape on the heel. It may be possible to frankenstien newer base plates on the old 997, but at that point, its probably not worth it and you should just use the newer bindings you're sourcing the parts from.