I would say that stocking would be fine for a 30g. I wouldn't use all of the substrate you have, but I'm sure you know that. The filter should be ok on a 30g. You might try to find a way to lessen the flow a little bit, maybe drill out the holes on the spray bar and make them a little larger.
As far as value, I would expect to get somewhere between $200-$300 for that setup.
As far as value, I would expect to get somewhere between $200-$300 for that setup.