Hi, so I am attempting to repair an old Marshall G10 MK. II amp and the only problem I can find is that all 3 of the pots are broken. All 3 of the pots are A50K and the controls are "Gain", "Contour", and "Volume". I really don't want to take the time and money to go out looking for A50K replacement pots seeing that this amp is old a cheap anyway, so I am wondering if I could use some A250K pots I have lying around without major consequence? Also what effect on the amp would A250K pots have if I do decide to do this? And yes I am sure there is no other problem with the amp.