Don't know what the value of the D130 will be, but the smallest deck designed for use with the X500 series is a 48" deck. However, the decks for the D series probably won't be a match for the X500 series. Best bet is to check with a dealer.
One would assume that a deck that would fit the x3 series would fit the x5. That would include both 42's and the 38. The rear arms may need to be changed. So if you need to stick with a 42 due to width constraints or to simplify bagging, hopefully your dealer can get it done & treat you right price wise too.