Broken keyboard rubber dome for SVI 738

Hi!
Is there anywhere I can find a replacement keyboard rubber dome for my newly bought SVI 738? The space key does not work properly. When i opened it up I found that the last owner(or who ever) have tried to fix it by exchanging the broken spacebar rubber dome part (that had worn out) with the graph key rubber part( by cutting and changing there places). Or is there any alternative way to fix it. The rubber dome part for the spacebar key is teared from the side.