No - I think it's immoral. Would you sell your blood or a kidney? There have been some gruesome cases abroad of people having been forced to sell a body part. OK, I know blood and milk are renewable but even so.
I would happily donate if there were a local milk bank.
ive donated to the hospital wher my dd was born as while i was there ive seen how precious it is, there was this girl who had herpes and could not breast feed her ds and thanks to other mums donating, her ds got the vital nutrients and antibodies in this milk, i could never sell it, and look at the price!!!!